Fixed things with switching moves; refactored code and removed extraneous resetSummonData calls

src/battle-scene.ts

@@ -872,48 +872,51 @@ export default class BattleScene extends SceneBase {
   }
 
   /**
-   * Return all {@linkcode Pokemon} that are **not** currently {@linkcode Pokemon.isOnField | on field}
+   * Return the party positions of all {@linkcode Pokemon} that are **not** currently {@linkcode Pokemon.isOnField | on field}
    * but are still {@linkcode Pokemon.isAllowedInBattle | allowed in battle}.
 
    * Used for switch out logic checks.
    * @param player - Whether to search the player (`true`) or enemy (`false`) party; default `true`
-   * @returns An array of all {@linkcode PlayerPokemon} in reserve able to be switched into.
+   * @returns An array containing the **INDICES** of all {@linkcode Pokemon} in reserve able to be switched into.
    * @overload
    */
-  public getBackupPartyMembers(player: true): PlayerPokemon[];
+  public getBackupPartyMemberIndices(player: true): number[];
   /**
-   * Return all {@linkcode Pokemon} that are **not** currently {@linkcode Pokemon.isOnField | on field}
+   * Return the party positions of all {@linkcode Pokemon} that are **not** currently {@linkcode Pokemon.isOnField | on field}
    * but are still {@linkcode Pokemon.isAllowedInBattle | allowed in battle}.
 
    * Used for switch out logic checks.
    * @param player - Whether to search the player (`true`) or enemy (`false`) party; default `true`
-   * @param trainerSlot - The {@linkcode EnemyPokemon.trainerSlot | trainer slot} of the Pokemon being switched out;
+   * @param trainerSlot - The {@linkcode TrainerSlot | trainer slot} to check against for enemy trainers;
    * used to verify ownership in multi battles.
-   * @returns An array of all {@linkcode EnemyPokemon} in reserve able to be switched into.
+   * @returns An array containing the **INDICES** of all {@linkcode Pokemon} in reserve able to be switched into.
    * @overload
    */
-  public getBackupPartyMembers(player: false, trainerSlot: number): EnemyPokemon[];
+  public getBackupPartyMemberIndices(player: false, trainerSlot: TrainerSlot): number[];
   /**
-   * Return all {@linkcode Pokemon} that are **not** currently {@linkcode Pokemon.isOnField | on field}
+   * Return the party positions of all {@linkcode Pokemon} that are **not** currently {@linkcode Pokemon.isOnField | on field}
    * but are still {@linkcode Pokemon.isAllowedInBattle | allowed in battle}.
 
    * Used for switch out logic checks.
    * @param player - Whether to search the player (`true`) or enemy (`false`) party; default `true`
-   * @param trainerSlot - The enemy Pokemon's {@linkcode EnemyPokemon.trainerSlot | trainer slot} for opposing trainers;
+   * @param trainerSlot - The {@linkcode TrainerSlot | trainer slot} to check against for enemy trainers;
    * used to verify ownership in multi battles and unused for player pokemon.
-   * @returns An array of all {@linkcode PlayerPokemon}/{@linkcode EnemyPokemon} in reserve able to be switched into.
+   * @returns An array containing the **INDICES** of all {@linkcode Pokemon} in reserve able to be switched into.
    * @overload
    */
-  public getBackupPartyMembers(player: boolean, trainerSlot: number | undefined): PlayerPokemon | EnemyPokemon[];
+  public getBackupPartyMemberIndices(player: boolean, trainerSlot: TrainerSlot | undefined): number[];
 
-  public getBackupPartyMembers<B extends boolean = never, R = B extends true ? PlayerPokemon : EnemyPokemon>(
+  public getBackupPartyMemberIndices(player: boolean, trainerSlot?: number): number[] {
-    player: B,
+    // Note: We return the indices instead of the actual Pokemon because `SwitchSummonPhase` and co. take an index instead of a pokemon.
-    trainerSlot?: number,
+    // If this is ever changed, this can be replaced with a simpler version involving `filter` and conditional type annotations.
-  ): R[] {
+    const indices: number[] = [];
-    return (player ? this.getPlayerParty() : this.getEnemyParty()).filter(
+    const party = player ? this.getPlayerParty() : this.getEnemyParty();
-      (p: PlayerPokemon | EnemyPokemon) =>
+    party.forEach((p: PlayerPokemon | EnemyPokemon, i: number) => {
-        p.isAllowedInBattle() && !p.isOnField() && (p instanceof PlayerPokemon || p.trainerSlot !== trainerSlot),
+      if (p.isAllowedInBattle() && !p.isOnField() && (player || (p as EnemyPokemon).trainerSlot === trainerSlot)) {
-    ) as R[];
+        indices.push(i);
+      }
+    });
+    return indices;
   }
 
   /**

src/data/abilities/ability.ts

@@ -80,6 +80,7 @@ import type { ArenaTrapTag, SuppressAbilitiesTag } from "#app/data/arena-tag";
 import { SelectBiomePhase } from "#app/phases/select-biome-phase";
 import { noAbilityTypeOverrideMoves } from "../moves/invalid-moves";
 import { ForceSwitch } from "../mixins/force-switch";
+import { MoveEffectPhase } from "#app/phases/move-effect-phase";
 
 export class BlockRecoilDamageAttr extends AbAttr {
   constructor() {
@@ -1301,7 +1302,6 @@ export class PokemonTypeChangeAbAttr extends PreAttackAbAttr {
     if (!pokemon.isTerastallized &&
     move.id !== Moves.STRUGGLE &&
     /**
-     * Skip moves that call other moves because these moves generate a following move that will trigger this ability attribute
      * @see {@link https://bulbapedia.bulbagarden.net/wiki/Category:Moves_that_call_other_moves}
      */
     !move.findAttr((attr) =>
@@ -2818,8 +2818,12 @@ export class CommanderAbAttr extends AbAttr {
 
     // TODO: Should this work with X + Dondozo fusions?
     const ally = pokemon.getAlly();
-    return globalScene.currentBattle?.double && !isNullOrUndefined(ally) && ally.species.speciesId === Species.DONDOZO
+    return (
-           && !(ally.isFainted() || ally.getTag(BattlerTagType.COMMANDED));
+      globalScene.currentBattle?.double
+      && ally?.species.speciesId === Species.DONDOZO
+      && !ally.isFainted()
+      && !ally.getTag(BattlerTagType.COMMANDED)
+    );
   }
 
   override apply(pokemon: Pokemon, passive: boolean, simulated: boolean, cancelled: null, args: any[]): void {
@@ -4105,7 +4109,6 @@ export class PostTurnRestoreBerryAbAttr extends PostTurnAbAttr {
       return false;
     }
 
-    // Clamp procChance to [0, 1]. Skip if didn't proc (less than pass)
     const pass = Phaser.Math.RND.realInRange(0, 1);
     return Phaser.Math.Clamp(this.procChance(pokemon), 0, 1) >= pass;
   }
@@ -5578,7 +5581,7 @@ export class PostDamageForceSwitchAbAttr extends ForceSwitch(PostDamageAbAttr) {
 
   constructor(switchType: NormalSwitchType = SwitchType.SWITCH, hpRatio = 0.5) {
     super();
-    this.selfSwitch = false; // TODO: change if any abilities get damage
+    this.selfSwitch = false; // TODO: change if any force switch abilities with red card exist
     this.switchType = switchType;
     this.hpRatio = hpRatio;
   }
@@ -5600,34 +5603,64 @@ export class PostDamageForceSwitchAbAttr extends ForceSwitch(PostDamageAbAttr) {
     source: Pokemon | undefined,
     _args: any[],
   ): boolean {
-    const userLastMove = pokemon.getLastXMoves()[0];
+
-    // Will not activate when the Pokémon's HP is lowered by cutting its own HP
+    // Skip move checks for damage not occurring due to a move (eg: hazards)
-    const forbiddenAttackingMoves = new Set<Moves>([ Moves.BELLY_DRUM, Moves.SUBSTITUTE, Moves.CURSE, Moves.PAIN_SPLIT ]);
+    const currentPhase = globalScene.getCurrentPhase();
-    if (!isNullOrUndefined(userLastMove) && forbiddenAttackingMoves.has(userLastMove.move)) {
+    if (currentPhase instanceof MoveEffectPhase && !this.passesMoveChecks(pokemon, source)) {
       return false;
     }
 
-    // Skip last move checks if no enemy move
+    if (!this.wasKnockedBelowHalf(pokemon, damage)) {
+      return false;
+    }
+
+    return this.canSwitchOut(pokemon)
+  }
+
+  /**
+   * Perform move checks to determine if this pokemon should switch out.
+   * @param pokemon - The {@linkcode Pokemon} with this ability
+   * @param source - The {@linkcode Pokemon} whose attack caused the user to switch out,
+   * or `undefined` if the damage source was indirect.
+   * @returns `true` if this Pokemon should be allowed to switch out.
+   */
+  private passesMoveChecks(pokemon: Pokemon, source: Pokemon | undefined): boolean {
+    // Wimp Out and Emergency Exit...
+    const currentPhase = globalScene.getCurrentPhase() as MoveEffectPhase;
+    const currentMove = currentPhase.move;
+
+    // will not activate from self-induced HP cutting...
+    // TODO: Verify that Fillet Away and Clangorous Soul proc wimp out
+    const hpCutMoves = new Set<Moves>([ Moves.CURSE, Moves.BELLY_DRUM, Moves.SUBSTITUTE, Moves.PAIN_SPLIT, Moves.CLANGOROUS_SOUL, Moves.FILLET_AWAY]);
+    // NB: Given this attribute is only applied after _taking damage_ or recieving a damaging attack,
+    // a failed Substitute or non-ghost type Curse will not trigger this ability to begin with.
+    const notHpCut = !hpCutMoves.has(currentMove.id)
+
+    // will not activate for forced switch moves (which trigger before wimp out activates)...
+    const notForceSwitched = ![Moves.DRAGON_TAIL, Moves.CIRCLE_THROW].includes(currentMove.id)
+
+    // and will not activate if the Pokemon is currently in the air from Sky Drop.
+    // TODO: Make this check the user's tags once Sky Drop is fully implemented -
+    // we could be sky dropped by another Pokemon or take indirect damage while skybound (both of which render this check moot)
     const lastMove = source?.getLastXMoves()[0]
-    if (
+    const notSkyDropped = !(lastMove?.move === Moves.SKY_DROP && lastMove.result === MoveResult.OTHER)
-      lastMove &&
-      // Will not activate for forced switch moves (triggers before wimp out activates)
-      (allMoves[lastMove.move].hasAttr(ForceSwitchOutAttr)
-      // Will not activate if the Pokémon's HP falls below half while it is in the air during Sky Drop
-      // TODO: Make this check the user's tags rather than the last move used by the target - we could be lifted by another pokemon
-      || (lastMove.move === Moves.SKY_DROP && lastMove.result === MoveResult.OTHER))
-    ) {
-      return false;
-    }
 
-    // Check for HP percents - don't switch if the move didn't knock us below our switch threshold
+    return notHpCut && notForceSwitched && notSkyDropped;
-    // (either because we were below it to begin with or are still above it after the hit).
+  }
+
+  /**
+   * Perform HP checks to determine if this pokemon should switch out.
+   * The switch fails if the pokemon was below {@linkcode hpRatio} before being hit
+   * or is still above it after the hit.
+   * @param pokemon - The {@linkcode Pokemon} with this ability
+   * @param damage - The amount of damage taken.
+   * @returns `true` if this Pokemon was knocked below half after `damage` was applied
+   */
+  private wasKnockedBelowHalf(pokemon: Pokemon, damage: number) {
+    // NB: This occurs in `MoveEffectPhase` _after_ attack damage has been dealt,
+    // so `pokemon.hp` contains the post-taking damage hp value.
     const hpNeededToSwitch = pokemon.getMaxHp() * this.hpRatio;
-    if (pokemon.hp + damage < hpNeededToSwitch || pokemon.hp >= hpNeededToSwitch) {
+    return pokemon.hp < hpNeededToSwitch && pokemon.hp + damage >= hpNeededToSwitch
-      return false;
-    }
-
-    return this.canSwitchOut(pokemon, undefined)
   }
 
   /**
@@ -6913,12 +6946,10 @@ export function initAbilities() {
       .attr(PostDefendStatStageChangeAbAttr, (target, user, move) => move.category !== MoveCategory.STATUS, Stat.DEF, 1),
     new Ability(Abilities.WIMP_OUT, 7)
       .attr(PostDamageForceSwitchAbAttr)
-      .condition(getSheerForceHitDisableAbCondition())
+      .condition(getSheerForceHitDisableAbCondition()),
-      .edgeCase(), // Should not trigger when hurting itself in confusion, causes Fake Out to fail turn 1 and succeed turn 2 if pokemon is switched out before battle start via playing in Switch Mode
     new Ability(Abilities.EMERGENCY_EXIT, 7)
       .attr(PostDamageForceSwitchAbAttr)
-      .condition(getSheerForceHitDisableAbCondition())
+      .condition(getSheerForceHitDisableAbCondition()),
-      .edgeCase(), // Should not trigger when hurting itself in confusion, causes Fake Out to fail turn 1 and succeed turn 2 if pokemon is switched out before battle start via playing in Switch Mode
     new Ability(Abilities.WATER_COMPACTION, 7)
       .attr(PostDefendStatStageChangeAbAttr, (target, user, move) => user.getMoveType(move) === PokemonType.WATER && move.category !== MoveCategory.STATUS, Stat.DEF, 2),
     new Ability(Abilities.MERCILESS, 7)

src/data/battler-tags.ts

@@ -751,10 +751,16 @@ export class ConfusedTag extends BattlerTag {
     );
   }
 
+  /**
+   * Tick down this Pokemon's confusion duration, randomly interrupting its move if not cured/
+   * @param pokemon - The {@linkcode Pokemon} with this tag
+   * @param lapseType - The {@linkcode BattlerTagLapseType | lapse type} triggering this tag's effects.
+   * @returns Whether the tag should be kept.
+   */
   lapse(pokemon: Pokemon, lapseType: BattlerTagLapseType): boolean {
-    const shouldLapse = lapseType !== BattlerTagLapseType.CUSTOM && super.lapse(pokemon, lapseType);
+    const shouldRemain = super.lapse(pokemon, lapseType);
 
-    if (!shouldLapse) {
+    if (!shouldRemain) {
       return false;
     }
 
@@ -766,7 +772,9 @@ export class ConfusedTag extends BattlerTag {
     globalScene.unshiftPhase(new CommonAnimPhase(pokemon.getBattlerIndex(), undefined, CommonAnim.CONFUSION));
 
     // 1/3 chance of hitting self with a 40 base power move
-    if (pokemon.randSeedInt(3) === 0 || Overrides.CONFUSION_ACTIVATION_OVERRIDE === true) {
+    const shouldInterruptMove = Overrides.CONFUSION_ACTIVATION_OVERRIDE ?? pokemon.randSeedInt(3) === 0;
+    if (shouldInterruptMove) {
+      // TODO: Are these calculations correct? We really shouldn't hardcode the damage formula here...
       const atk = pokemon.getEffectiveStat(Stat.ATK);
       const def = pokemon.getEffectiveStat(Stat.DEF);
       const damage = toDmgValue(

src/data/mixins/force-switch.ts

@@ -17,51 +17,49 @@ import { applyAbAttrs, ForceSwitchOutImmunityAbAttr } from "../abilities/ability
 import type { MoveAttr } from "../moves/move";
 import { getPokemonNameWithAffix } from "#app/messages";
 import type { AbAttr } from "../abilities/ab-attrs/ab-attr";
-import type { TrainerSlot } from "#enums/trainer-slot";
 
-// NB: This shouldn't be terribly hard to extend from if switching items are added (à la Eject Button)
+// NB: This shouldn't be terribly hard to extend from items if switching items are added (à la Eject Button/Red Card);
 type SubMoveOrAbAttr = (new (...args: any[]) => MoveAttr) | (new (...args: any[]) => AbAttr);
 
-/** Mixin to handle shared logic for switch-in moves and abilities. */
+/** Mixin to handle shared logic for switching moves and abilities. */
 export function ForceSwitch<TBase extends SubMoveOrAbAttr>(Base: TBase) {
   return class ForceSwitchClass extends Base {
     protected selfSwitch = false;
     protected switchType: NormalSwitchType = SwitchType.SWITCH;
 
     /**
-     * Determines if a Pokémon can be forcibly switched out based on its status, the opponent's status and battle conditions.
+     * Determines if a Pokémon can be forcibly switched out based on its status and battle conditions.
-     * @see {@linkcode performOpponentChecks} for opponent-related check code.
+     * @param switchOutTarget - The {@linkcode Pokemon} being switched out.
-
-     * @param switchOutTarget - The {@linkcode Pokemon} attempting to switch out.
-     * @param opponent - The {@linkcode Pokemon} opposing the currently switched out Pokemon.
-     * Unused if {@linkcode selfSwitch} is `true`, as it is only used to check Suction Cups.
      * @returns Whether {@linkcode switchOutTarget} can be switched out by the current Move or Ability.
      */
-    protected canSwitchOut(switchOutTarget: Pokemon, opponent: Pokemon | undefined): boolean {
+    protected canSwitchOut(switchOutTarget: Pokemon): boolean {
       const isPlayer = switchOutTarget instanceof PlayerPokemon;
 
-      if (!this.selfSwitch && opponent && !this.performOpponentChecks(switchOutTarget, opponent)) {
+      // If we aren't switching ourself out, ensure the target in question can actually be switched out by us
+      if (!this.selfSwitch && !this.performForceSwitchChecks(switchOutTarget)) {
         return false;
       }
 
+      // Wild enemies should not be allowed to flee with baton pass, nor by any means on X0 waves (don't want easy boss wins)
       if (!isPlayer && globalScene.currentBattle.battleType === BattleType.WILD) {
-        // enemies should not be allowed to flee with baton pass, nor by any means on X0 waves (don't want easy boss wins)
         return this.switchType !== SwitchType.BATON_PASS && globalScene.currentBattle.waveIndex % 10 !== 0;
       }
 
-      // Finally, ensure that we have valid switch out targets.
+      // Finally, ensure that a trainer switching out has at least 1 valid reserve member to send in.
-      const reservePartyMembers = globalScene.getBackupPartyMembers(
+      const reservePartyMembers = globalScene.getBackupPartyMemberIndices(
         isPlayer,
-        (switchOutTarget as EnemyPokemon).trainerSlot as TrainerSlot | undefined,
+        !isPlayer ? (switchOutTarget as EnemyPokemon).trainerSlot : undefined,
-      ); // evaluates to `undefined` if not present
+      );
-      if (reservePartyMembers.length === 0) {
+      return reservePartyMembers.length > 0;
-        return false;
-      }
-
-      return true;
     }
 
-    protected performOpponentChecks(switchOutTarget: Pokemon, opponent: Pokemon): boolean {
+    /**
+     * Perform various checks to confirm the switched out target can be forcibly removed from the field
+     * by another Pokemon.
+     * @param switchOutTarget - The {@linkcode Pokemon} being switched out
+     * @returns Whether {@linkcode switchOutTarget} can be switched out by another Pokemon.
+     */
+    private performForceSwitchChecks(switchOutTarget: Pokemon): boolean {
       // Dondozo with an allied Tatsugiri in its mouth cannot be forced out by enemies
       const commandedTag = switchOutTarget.getTag(BattlerTagType.COMMANDED);
       if (commandedTag?.getSourcePokemon()?.isActive(true)) {
@@ -70,8 +68,8 @@ export function ForceSwitch<TBase extends SubMoveOrAbAttr>(Base: TBase) {
 
       // Check for opposing switch block abilities (Suction Cups and co)
       const blockedByAbility = new BooleanHolder(false);
-      applyAbAttrs(ForceSwitchOutImmunityAbAttr, opponent, blockedByAbility);
+      applyAbAttrs(ForceSwitchOutImmunityAbAttr, switchOutTarget, blockedByAbility);
-      if (!blockedByAbility.value) {
+      if (blockedByAbility.value) {
         return false;
       }
 
@@ -97,7 +95,10 @@ export function ForceSwitch<TBase extends SubMoveOrAbAttr>(Base: TBase) {
       }
 
       if (!(switchOutTarget instanceof EnemyPokemon)) {
-        console.warn("Switched out target not instance of Player or enemy Pokemon!");
+        console.warn(
+          "Switched out target (index %i) neither player nor enemy Pokemon!",
+          switchOutTarget.getFieldIndex(),
+        );
         return;
       }
 
@@ -119,12 +120,12 @@ export function ForceSwitch<TBase extends SubMoveOrAbAttr>(Base: TBase) {
         return;
       }
 
-      // Pick a random player pokemon to switch out.
+      // Pick a random eligible player pokemon to replace the switched out one.
-      const reservePartyMembers = globalScene.getBackupPartyMembers(true);
+      const reservePartyMembers = globalScene.getBackupPartyMemberIndices(true);
-      const switchOutIndex = switchOutTarget.randSeedInt(reservePartyMembers.length);
+      const switchInIndex = reservePartyMembers[switchOutTarget.randSeedInt(reservePartyMembers.length)];
 
       globalScene.appendToPhase(
-        new SwitchSummonPhase(this.switchType, switchOutTarget.getFieldIndex(), switchOutIndex, false, true),
+        new SwitchSummonPhase(this.switchType, switchOutTarget.getFieldIndex(), switchInIndex, false, true),
         MoveEndPhase,
       );
     }
@@ -132,15 +133,16 @@ export function ForceSwitch<TBase extends SubMoveOrAbAttr>(Base: TBase) {
     private trySwitchTrainerPokemon(switchOutTarget: EnemyPokemon): void {
       // fallback for no trainer
       if (!globalScene.currentBattle.trainer) {
-        console.warn("Enemy trainer switch logic approached without a trainer!");
+        console.warn("Enemy trainer switch logic triggered without a trainer!");
         return;
       }
-      // Forced switches will to pick a random eligible pokemon, while
+
-      // choice-based switching uses the trainer's default switch behavior
+      // Forced switches will pick a random eligible pokemon from this trainer's side, while
-      const reservePartyMembers = globalScene.getBackupPartyMembers(false, switchOutTarget.trainerSlot);
+      // choice-based switching uses the trainer's default switch behavior.
+      const reservePartyIndices = globalScene.getBackupPartyMemberIndices(false, switchOutTarget.trainerSlot);
       const summonIndex =
         this.switchType === SwitchType.FORCE_SWITCH
-          ? switchOutTarget.randSeedInt(reservePartyMembers.length)
+          ? reservePartyIndices[switchOutTarget.randSeedInt(reservePartyIndices.length)]
           : (globalScene.currentBattle.trainer.getNextSummonIndex(switchOutTarget.trainerSlot) ?? 0);
       globalScene.appendToPhase(
         new SwitchSummonPhase(this.switchType, switchOutTarget.getFieldIndex(), summonIndex, false, false),
@@ -180,5 +182,9 @@ export function ForceSwitch<TBase extends SubMoveOrAbAttr>(Base: TBase) {
     public isBatonPass(): boolean {
       return this.switchType === SwitchType.BATON_PASS;
     }
+
+    public isForcedSwitch(): boolean {
+      return this.switchType === SwitchType.FORCE_SWITCH;
+    }
   };
 }

src/data/moves/move.ts

@@ -2002,6 +2002,13 @@ export class FlameBurstAttr extends MoveEffectAttr {
   }
 }
 
+/**
+ * Attribute to KO the user while fully restoring HP/status of the next switched in Pokemon.
+ *
+ * Used for {@linkcode Moves.HEALING_WISH} and {@linkcode Moves.LUNAR_DANCE}.
+ * TODO: Implement "heal storing" if switched in pokemon is at full HP (likely with an end-of-turn ArenaTag).
+ * Will likely be blocked by the need for a "slot dependent ArenaTag" similar to Future Sight
+ */
 export class SacrificialFullRestoreAttr extends SacrificialAttr {
   protected restorePP: boolean;
   protected moveMessage: string;
@@ -2019,8 +2026,8 @@ export class SacrificialFullRestoreAttr extends SacrificialAttr {
     }
 
     // We don't know which party member will be chosen, so pick the highest max HP in the party
-    const party = user.isPlayer() ? globalScene.getPlayerParty() : globalScene.getEnemyParty();
+    const party: Pokemon[] = user.isPlayer() ? globalScene.getPlayerParty() : globalScene.getEnemyParty();
-    const maxPartyMemberHp = party.map(p => p.getMaxHp()).reduce((maxHp: number, hp: number) => Math.max(hp, maxHp), 0);
+    const maxPartyMemberHp = Math.max(...party.map(p => p.getMaxHp()));
 
     globalScene.pushPhase(
       new PokemonHealPhase(
@@ -6210,7 +6217,9 @@ export class RevivalBlessingAttr extends MoveEffectAttr {
   }
 }
 
-
+/**
+ * Attribute to forcibly switch out the user or target of a Move.
+ */
 export class ForceSwitchOutAttr extends ForceSwitch(MoveEffectAttr) {
   constructor(
     selfSwitch: boolean = false,
@@ -6221,54 +6230,67 @@ export class ForceSwitchOutAttr extends ForceSwitch(MoveEffectAttr) {
     this.switchType = switchType;
   }
 
-  apply(user: Pokemon, target: Pokemon, _move: Move, _args: any[]): boolean {
+  apply(user: Pokemon, target: Pokemon, move: Move, _args: any[]): boolean {
+    if (!this.getSwitchOutCondition()(user, target, move)) {
+      return false;
+    }
     this.doSwitch(this.selfSwitch ? user : target)
     return true;
   }
 
   getCondition(): MoveConditionFunc {
-    return this.getSwitchOutCondition();
+    // Damaging switch moves should not "fail" _per se_ upon a failed switch -
+    // they still succeed and deal damage (but just without actually switching out).
+    return (user, target, move) => (move.category !== MoveCategory.STATUS || this.getSwitchOutCondition()(user, target, move));
   }
 
+  /**
+   * Check whether the target can be switched out.
+   * @returns A {@linkcode MoveConditionFunc} that returns `true` if the switch out attempt should succeed.
+   */
   getSwitchOutCondition(): MoveConditionFunc {
     return (user, target, move) => {
-      const [switchOutTarget, opponent] = this.selfSwitch ? [user, target] : [target, user];
+      const switchOutTarget = this.selfSwitch ? user : target;
 
       // Don't allow wild mons to flee with U-turn et al.
-      if (switchOutTarget instanceof EnemyPokemon && globalScene.currentBattle.battleType === BattleType.WILD && !(this.selfSwitch && move.category !== MoveCategory.STATUS)) {
+      if (
+        switchOutTarget instanceof EnemyPokemon
+        && globalScene.currentBattle.battleType === BattleType.WILD
+        && this.selfSwitch
+        && move.category !== MoveCategory.STATUS
+      ) {
         return false;
       }
 
-      return this.canSwitchOut(switchOutTarget, opponent)
+      // Check for Wimp Out edge case - self-switching moves cannot proc if the attack also triggers Wimp Out/EE
+      const moveDmgDealt = user.turnData.lastMoveDamageDealt[target.getBattlerIndex()]
+      if (
+        this.selfSwitch
+        && moveDmgDealt
+        && target.getAbilityAttrs(PostDamageForceSwitchAbAttr).some(
+          p => p.canApplyPostDamage(target, moveDmgDealt, false, user, []))
+        ) {
+          return false;
+        }
+
+      return this.canSwitchOut(switchOutTarget)
     };
   }
 
   getUserBenefitScore(user: Pokemon, target: Pokemon, move: Move): number {
-    if (!globalScene.getEnemyParty().find(p => p.isActive() && !p.isOnField())) {
+    const reservePartyMembers = globalScene.getBackupPartyMemberIndices(user.isPlayer() === this.selfSwitch, !user.isPlayer() ? (user as EnemyPokemon).trainerSlot : undefined)
+    if (reservePartyMembers.length === 0) {
       return -20;
     }
+
     let ret = this.selfSwitch ? Math.floor((1 - user.getHpRatio()) * 20) : super.getUserBenefitScore(user, target, move);
     if (this.selfSwitch && this.isBatonPass()) {
       const statStageTotal = user.getStatStages().reduce((s: number, total: number) => total += s, 0);
+      // TODO: Why do we use a sine tween?
       ret = ret / 2 + (Phaser.Tweens.Builders.GetEaseFunction("Sine.easeOut")(Math.min(Math.abs(statStageTotal), 10) / 10) * (statStageTotal >= 0 ? 10 : -10));
     }
     return ret;
   }
-
-  /**
-  * Helper function to check if the Pokémon's health is below half after taking damage.
-  * Used for an edge case interaction with Wimp Out/Emergency Exit.
-  * If the Ability activates due to being hit by U-turn or Volt Switch, the user of that move will not be switched out.
-  */
-  hpDroppedBelowHalf(target: Pokemon): boolean {
-    const pokemonHealth = target.hp;
-    const maxPokemonHealth = target.getMaxHp();
-    const damageTaken = target.turnData.damageTaken;
-    const initialHealth = pokemonHealth + damageTaken;
-
-    // Check if the Pokémon's health has dropped below half after the damage
-    return initialHealth >= maxPokemonHealth / 2 && pokemonHealth < maxPokemonHealth / 2;
-  }
 }
 
 export class ChillyReceptionAttr extends ForceSwitchOutAttr {

src/data/mystery-encounters/mystery-encounter.ts

@@ -344,12 +344,13 @@ export default class MysteryEncounter implements IMysteryEncounter {
    */
   private meetsPrimaryRequirementAndPrimaryPokemonSelected(): boolean {
     let qualified: PlayerPokemon[] = globalScene.getPlayerParty();
-    if (!this.primaryPokemonRequirements || this.primaryPokemonRequirements.length === 0) {
+    if (!this.primaryPokemonRequirements?.length) {
       // If we lack specified criterion, grab the first on-field pokemon, or else the first pokemon allowed in battle
       const activeMons = qualified.filter(p => p.isAllowedInBattle());
       this.primaryPokemon = activeMons.find(p => p.isOnField()) ?? activeMons[0];
       return true;
     }
+
     for (const req of this.primaryPokemonRequirements) {
       if (req.meetsRequirement()) {
         qualified = qualified.filter(pkmn => req.queryParty(globalScene.getPlayerParty()).includes(pkmn));

src/field/pokemon.ts

@@ -4757,7 +4757,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
    * @param ignoreFaintPhase - Whether to ignore adding a faint phase if the damage causes the target to faint; default `false`
    * @returns The amount of damage actually dealt.
    * @remarks
-   * This will not trigger "on damage" effects for direct damage moves, which instead occurs at the end of `MoveEffectPhase`.
+   * This will not trigger "on damage" effects for direct damage moves, instead occuring at the end of `MoveEffectPhase`.
    */
   damageAndUpdate(damage: number,
     {
@@ -4782,7 +4782,8 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
     );
     globalScene.unshiftPhase(damagePhase);
 
-    // TODO: Review if wimp out battle skip actually needs this anymore
+    // Prevent enemies not on field from taking damage.
+    // TODO: Review if wimp out actually needs this anymore
     if (this.switchOutStatus) {
       damage = 0;
     }
@@ -4803,8 +4804,9 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
     // Damage amount may have changed, but needed to be queued before calling damage function
     damagePhase.updateAmount(damage);
 
-    // Trigger PostDamageAbAttr (ie wimp out) for indirect damage only.
+    // Trigger PostDamageAbAttr (ie wimp out) for indirect, non-confusion damage instances.
-    if (isIndirectDamage) {
+    // We leave `source` as undefined for indirect hits to specify that the damage instance is indirect.
+    if (isIndirectDamage && result !== HitResult.CONFUSION) {
       applyPostDamageAbAttrs(
         PostDamageAbAttr,
         this,
@@ -5726,8 +5728,8 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
    * Reset this Pokemon's {@linkcode PokemonSummonData | SummonData} and {@linkcode PokemonTempSummonData | TempSummonData}
    * in preparation for switching pokemon, as well as removing any relevant on-switch tags.
    * @remarks
-   * This **SHOULD NOT** be called when a `SummonPhase` or `SwitchSummonPhase` is already being added,
+   * This **SHOULD NOT** be called when {@linkcode leaveField} is already being called,
-   * both of which call this method (directly or indirectly) on both pokemon changing positions.
+   * which already calls this function.
    */
   resetSummonData(): void {
     console.log(`resetSummonData called on Pokemon ${this.name}`)
@@ -5801,6 +5803,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
   }
 
   resetTurnData(): void {
+    console.log(`resetTurnData called on Pokemon ${this.name}`)
     this.turnData = new PokemonTurnData();
   }
 
@@ -6311,7 +6314,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
    * @param destroy - Whether to destroy this Pokemon once it leaves the field; default `false`
    * @remarks
    * This **SHOULD NOT** be called when a `SummonPhase` or `SwitchSummonPhase` is already being added,
-   * which can lead to erroneous resetting of {@linkcode turnData} or {@linkcode summonData}.
+   * which can lead to premature resetting of {@klinkcode turnData} and {@linkcode summonData}.
    */
   leaveField(clearEffects = true, hideInfo = true, destroy = false) {
     console.log(`leaveField called on Pokemon ${this.name}`)
@@ -7960,12 +7963,20 @@ export class PokemonTurnData {
    */
   public hitsLeft = -1;
   /**
-   * The amount of damage dealt by this Pokemon's last attack.
+   * The final amount of damage dealt by this Pokemon's last attack against each of its targets,
-   * Reset upon successfully using a move and used to enable internal tracking of damage amounts.
+   * mapped by their respective `BattlerIndex`es.
+   * Reset to an empty array upon attempting to use a move,
+   * and is used to calculate various damage-related effects (Shell Bell, U-Turn + Wimp Out interactions, etc.).
+   */
+  public lastMoveDamageDealt: number[] = [];
+  /**
+   * The amount of damage dealt by this Pokemon's last hit.
+   * Used to calculate recoil damage amounts.
+   * TODO: Merge with `lastMoveDamageDealt` if any spread recoil moves are added
    */
-  public lastMoveDamageDealt = 0;
   public singleHitDamageDealt = 0;
-  // TODO: Rework this into "damage taken last" counter for metal burst and co.
+  // TODO: Make this into a "damage taken last" counter for metal burst and co.
+  // This is currently ONLY USED FOR ASSURANCE
   public damageTaken = 0;
   public attacksReceived: AttackMoveResult[] = [];
   public order: number;

src/modifier/modifier.ts

@@ -1783,21 +1783,22 @@ export class HitHealModifier extends PokemonHeldItemModifier {
    * @returns `true` if the {@linkcode Pokemon} was healed
    */
   override apply(pokemon: Pokemon): boolean {
-    if (pokemon.turnData.lastMoveDamageDealt && !pokemon.isFullHp()) {
+    if (pokemon.isFullHp()) {
-      // TODO: this shouldn't be undefined AFAIK
+      return false;
-      globalScene.unshiftPhase(
-        new PokemonHealPhase(
-          pokemon.getBattlerIndex(),
-          toDmgValue(pokemon.turnData.lastMoveDamageDealt / 8) * this.stackCount,
-          i18next.t("modifier:hitHealApply", {
-            pokemonNameWithAffix: getPokemonNameWithAffix(pokemon),
-            typeName: this.type.name,
-          }),
-          true,
-        ),
-      );
     }
 
+    const totalDmgDealt = pokemon.turnData.lastMoveDamageDealt.reduce((r, d) => r + d, 0);
+    globalScene.unshiftPhase(
+      new PokemonHealPhase(
+        pokemon.getBattlerIndex(),
+        toDmgValue(totalDmgDealt / 8) * this.stackCount,
+        i18next.t("modifier:hitHealApply", {
+          pokemonNameWithAffix: getPokemonNameWithAffix(pokemon),
+          typeName: this.type.name,
+        }),
+        true,
+      ),
+    );
     return true;
   }
 

src/phases/faint-phase.ts

@@ -61,8 +61,6 @@ export class FaintPhase extends PokemonPhase {
       faintPokemon.getTag(BattlerTagType.GRUDGE)?.lapse(faintPokemon, BattlerTagLapseType.CUSTOM, this.source);
     }
 
-    faintPokemon.resetSummonData();
-
     if (!this.preventInstantRevive) {
       const instantReviveModifier = globalScene.applyModifier(
         PokemonInstantReviveModifier,
@@ -71,6 +69,7 @@ export class FaintPhase extends PokemonPhase {
       ) as PokemonInstantReviveModifier;
 
       if (instantReviveModifier) {
+        faintPokemon.resetSummonData();
         faintPokemon.loseHeldItem(instantReviveModifier);
         globalScene.updateModifiers(this.player);
         return this.end();

src/phases/move-effect-phase.ts

@@ -3,6 +3,7 @@ import { globalScene } from "#app/global-scene";
 import {
   AddSecondStrikeAbAttr,
   AlwaysHitAbAttr,
+  applyAbAttrs,
   applyPostAttackAbAttrs,
   applyPostDamageAbAttrs,
   applyPostDefendAbAttrs,
@@ -78,6 +79,7 @@ import type Move from "#app/data/moves/move";
 import { isFieldTargeted } from "#app/data/moves/move-utils";
 import { FaintPhase } from "./faint-phase";
 import { DamageAchv } from "#app/system/achv";
+import { userInfo } from "node:os";
 
 type HitCheckEntry = [HitCheckResult, TypeDamageMultiplier];
 
@@ -95,7 +97,7 @@ export class MoveEffectPhase extends PokemonPhase {
 
   /** Is this the first strike of a move? */
   private firstHit: boolean;
-  /** Is this the last strike of a move? */
+  /** Is this the last strike of a move (either due to running out of hits or all targets being fainted/immune)? */
   private lastHit: boolean;
 
   /** Phases queued during moves */
@@ -181,7 +183,6 @@ export class MoveEffectPhase extends PokemonPhase {
    * Queue the phaes that should occur when the target reflects the move back to the user
    * @param user - The {@linkcode Pokemon} using this phase's invoked move
    * @param target - The {@linkcode Pokemon} that is reflecting the move
-   *
    */
   private queueReflectedMove(user: Pokemon, target: Pokemon): void {
     const newTargets = this.move.isMultiTarget()
@@ -342,7 +343,7 @@ export class MoveEffectPhase extends PokemonPhase {
     const targets = this.conductHitChecks(user, fieldMove);
 
     this.firstHit = user.turnData.hitCount === user.turnData.hitsLeft;
-    this.lastHit = user.turnData.hitsLeft === 1 || !targets.some(t => t.isActive(true));
+    this.lastHit = user.turnData.hitsLeft === 1 || targets.every(t => !t.isActive(true));
 
     // Play the animation if the move was successful against any of its targets or it has a POST_TARGET effect (like self destruct)
     if (
@@ -766,6 +767,7 @@ export class MoveEffectPhase extends PokemonPhase {
    * - Triggering form changes and emergency exit / wimp out if this is the last hit
    *
    * @param target - the {@linkcode Pokemon} hit by this phase's move.
+   * @param targetIndex - The index of the target (used to update damage dealt amounts)
    * @param effectiveness - The effectiveness of the move (as previously evaluated in {@linkcode hitCheck})
    * @param firstTarget - Whether this is the first target successfully struck by the move
    */
@@ -785,7 +787,13 @@ export class MoveEffectPhase extends PokemonPhase {
     }
     if (this.lastHit) {
       globalScene.triggerPokemonFormChange(user, SpeciesFormChangePostMoveTrigger);
-      applyPostDamageAbAttrs(PostDamageAbAttr, target, target.turnData.lastMoveDamageDealt);
+      applyPostDamageAbAttrs(
+        PostDamageAbAttr,
+        target,
+        user.turnData.lastMoveDamageDealt[target.getBattlerIndex()],
+        false,
+        user,
+      );
     }
   }
 
@@ -863,7 +871,7 @@ export class MoveEffectPhase extends PokemonPhase {
       globalScene.gameData.gameStats.highestDamage = Math.max(damage, globalScene.gameData.gameStats.highestDamage);
     }
 
-    user.turnData.lastMoveDamageDealt += damage;
+    user.turnData.lastMoveDamageDealt[target.getBattlerIndex()] += damage;
     user.turnData.singleHitDamageDealt = damage;
     target.battleData.hitCount++;
     // TODO: this might be incorrect for counter moves

src/phases/move-phase.ts

@@ -43,7 +43,7 @@ import { CommonAnimPhase } from "#app/phases/common-anim-phase";
 import { MoveChargePhase } from "#app/phases/move-charge-phase";
 import { MoveEffectPhase } from "#app/phases/move-effect-phase";
 import { MoveEndPhase } from "#app/phases/move-end-phase";
-import { NumberHolder } from "#app/utils/common";
+import { getEnumValues, NumberHolder } from "#app/utils/common";
 import { Abilities } from "#enums/abilities";
 import { ArenaTagType } from "#enums/arena-tag-type";
 import { BattlerTagType } from "#enums/battler-tag-type";
@@ -160,7 +160,7 @@ export class MovePhase extends BattlePhase {
     }
 
     this.pokemon.turnData.acted = true;
-    this.pokemon.turnData.lastMoveDamageDealt = 0;
+    this.pokemon.turnData.lastMoveDamageDealt = Array(Math.max(...getEnumValues(BattlerIndex))).fill(0);
 
     // Reset hit-related turn data when starting follow-up moves (e.g. Metronomed moves, Dancer repeats)
     if (this.followUp) {

src/phases/summon-phase.ts

@@ -274,6 +274,7 @@ export class SummonPhase extends PartyMemberPokemonPhase {
       globalScene.unshiftPhase(new ShinySparklePhase(pokemon.getBattlerIndex()));
     }
 
+    // TODO: This might be a duplicate - check to see if can be removed without breaking things
     pokemon.resetTurnData();
 
     if (

src/phases/switch-phase.ts

@@ -37,7 +37,7 @@ export class SwitchPhase extends BattlePhase {
     super.start();
 
     // Failsafe: skip modal switches if impossible (no eligible party members in reserve).
-    if (this.isModal && globalScene.getBackupPartyMembers(true).length === 0) {
+    if (this.isModal && globalScene.getBackupPartyMemberIndices(true).length === 0) {
       return super.end();
     }
 
@@ -52,11 +52,11 @@ export class SwitchPhase extends BattlePhase {
       return super.end();
     }
 
-    // Check if there is any space still in field
+    // Check if there is any space still on field.
+    // TODO: Do we need this?
     if (
       this.isModal &&
-      globalScene.getPlayerField().filter(p => p.isAllowedInBattle() && p.isActive(true)).length >=
+      globalScene.getPlayerField().filter(p => p.isActive(true)).length > globalScene.currentBattle.getBattlerCount()
-        globalScene.currentBattle.getBattlerCount()
     ) {
       return super.end();
     }

src/phases/switch-summon-phase.ts

@@ -2,18 +2,15 @@ import { globalScene } from "#app/global-scene";
 import {
   applyPreSummonAbAttrs,
   applyPreSwitchOutAbAttrs,
-  PostDamageForceSwitchAbAttr,
   PreSummonAbAttr,
   PreSwitchOutAbAttr,
 } from "#app/data/abilities/ability";
-import { allMoves, ForceSwitchOutAttr } from "#app/data/moves/move";
 import { getPokeballTintColor } from "#app/data/pokeball";
 import { SpeciesFormChangeActiveTrigger } from "#app/data/pokemon-forms";
 import { TrainerSlot } from "#enums/trainer-slot";
 import type Pokemon from "#app/field/pokemon";
 import { getPokemonNameWithAffix } from "#app/messages";
 import { SwitchEffectTransferModifier } from "#app/modifier/modifier";
-import { Command } from "#app/ui/command-ui-handler";
 import i18next from "i18next";
 import { PostSummonPhase } from "./post-summon-phase";
 import { SummonPhase } from "./summon-phase";
@@ -74,13 +71,13 @@ export class SwitchSummonPhase extends SummonPhase {
       return;
     }
 
-    const pokemon = this.getPokemon();
+    const lastPokemon = this.getPokemon();
     (this.player ? globalScene.getEnemyField() : globalScene.getPlayerField()).forEach(enemyPokemon =>
-      enemyPokemon.removeTagsBySourceId(pokemon.id),
+      enemyPokemon.removeTagsBySourceId(lastPokemon.id),
     );
 
     if (this.switchType === SwitchType.SWITCH || this.switchType === SwitchType.INITIAL_SWITCH) {
-      const substitute = pokemon.getTag(SubstituteTag);
+      const substitute = lastPokemon.getTag(SubstituteTag);
       if (substitute) {
         globalScene.tweens.add({
           targets: substitute.sprite,
@@ -95,26 +92,26 @@ export class SwitchSummonPhase extends SummonPhase {
     globalScene.ui.showText(
       this.player
         ? i18next.t("battle:playerComeBack", {
-            pokemonName: getPokemonNameWithAffix(pokemon),
+            pokemonName: getPokemonNameWithAffix(lastPokemon),
           })
         : i18next.t("battle:trainerComeBack", {
             trainerName: globalScene.currentBattle.trainer?.getName(
               !(this.fieldIndex % 2) ? TrainerSlot.TRAINER : TrainerSlot.TRAINER_PARTNER,
             ),
-            pokemonName: pokemon.getNameToRender(),
+            pokemonName: lastPokemon.getNameToRender(),
           }),
     );
     globalScene.playSound("se/pb_rel");
-    pokemon.hideInfo();
+    lastPokemon.hideInfo();
-    pokemon.tint(getPokeballTintColor(pokemon.getPokeball(true)), 1, 250, "Sine.easeIn");
+    lastPokemon.tint(getPokeballTintColor(lastPokemon.getPokeball(true)), 1, 250, "Sine.easeIn");
     globalScene.tweens.add({
-      targets: pokemon,
+      targets: lastPokemon,
       duration: 250,
       ease: "Sine.easeIn",
       scale: 0.5,
       onComplete: () => {
         globalScene.time.delayedCall(750, () => this.switchAndSummon());
-        pokemon.leaveField(this.switchType === SwitchType.SWITCH, false);
+        lastPokemon.leaveField(this.switchType === SwitchType.SWITCH, false);
       },
     });
   }
@@ -192,8 +189,6 @@ export class SwitchSummonPhase extends SummonPhase {
           switchedInPokemon.y += this.lastPokemon.getSubstituteOffset()[1];
           switchedInPokemon.setAlpha(0.5);
         }
-      } else {
-        switchedInPokemon.resetSummonData();
       }
       this.summon();
     };
@@ -214,26 +209,6 @@ export class SwitchSummonPhase extends SummonPhase {
 
     const pokemon = this.getPokemon();
 
-    const moveId = globalScene.currentBattle.lastMove;
-    const lastUsedMove = moveId ? allMoves[moveId] : undefined;
-
-    const currentCommand = globalScene.currentBattle.turnCommands[this.fieldIndex]?.command;
-    const lastPokemonIsForceSwitchedAndNotFainted =
-      lastUsedMove?.hasAttr(ForceSwitchOutAttr) && !this.lastPokemon.isFainted();
-    const lastPokemonHasForceSwitchAbAttr =
-      this.lastPokemon.hasAbilityWithAttr(PostDamageForceSwitchAbAttr) && !this.lastPokemon.isFainted();
-
-    // Compensate for turn spent summoning/forced switch if switched out pokemon is not fainted.
-    // Needed as we increment turn counters in `TurnEndPhase`.
-    if (
-      currentCommand === Command.POKEMON ||
-      lastPokemonIsForceSwitchedAndNotFainted ||
-      lastPokemonHasForceSwitchAbAttr
-    ) {
-      pokemon.tempSummonData.turnCount--;
-      pokemon.tempSummonData.waveTurnCount--;
-    }
-
     if (this.switchType === SwitchType.BATON_PASS && pokemon) {
       pokemon.transferSummon(this.lastPokemon);
     } else if (this.switchType === SwitchType.SHED_TAIL && pokemon) {
@@ -243,14 +218,17 @@ export class SwitchSummonPhase extends SummonPhase {
       }
     }
 
-    // Reset turn data if not initial switch (since it gets initialized to an empty object on turn start)
+    // If not switching at start of battle, reset turn counts and temp data.
+    // Needed as we increment turn counters in `TurnEndPhase`.
     if (this.switchType !== SwitchType.INITIAL_SWITCH) {
+      pokemon.tempSummonData.turnCount--;
+      pokemon.tempSummonData.waveTurnCount--;
+      // No need to reset turn/summon data for initial switch since both get initialized to an empty object on object creation
       pokemon.resetTurnData();
+      pokemon.resetSummonData();
       pokemon.turnData.switchedInThisTurn = true;
     }
 
-    this.lastPokemon.resetSummonData();
-
     globalScene.triggerPokemonFormChange(pokemon, SpeciesFormChangeActiveTrigger, true);
     // Reverts to weather-based forms when weather suppressors (Cloud Nine/Air Lock) are switched out
     globalScene.arena.triggerWeatherBasedFormChanges();

src/utils/common.ts

@@ -566,3 +566,55 @@ export function animationFileName(move: Moves): string {
 export function camelCaseToKebabCase(str: string): string {
   return str.replace(/[A-Z]+(?![a-z])|[A-Z]/g, (s, o) => (o ? "-" : "") + s.toLowerCase());
 }
+
+/**
+ * Split an array into a pair of arrays based on a conditional function.
+ * @param array - The array to split into 2.
+ * @param predicate - A function accepting up to 3 arguments. The split function calls the predicate function once per element of the array.
+ * @param thisArg -  An object to which the this keyword can refer in the predicate function. If thisArg is omitted, `undefined` is used as the this value.
+ * @returns A pair of shallowly-copied arrays containing every element for which `predicate` did or did not return a value coercible to the boolean `true`.
+ */
+export function splitArray<T, S extends T>(
+  array: T[],
+  predicate: (value: T, index: number, array: T[]) => value is S,
+  thisArg?: unknown,
+): [matches: S[], nonMatches: S[]];
+
+/**
+ * Split an array into a pair of arrays based on a conditional function.
+ * @param array - The array to split into 2.
+ * @param predicate - A function accepting up to 3 arguments. The split function calls the function once per element of the array.
+ * @param thisArg -  An object to which the this keyword can refer in the predicate function. If thisArg is omitted, `undefined` is used as the this value.
+ * @returns A pair of shallowly-copied arrays containing every element for which `predicate` did or did not return a value coercible to the boolean `true`.
+ */
+export function splitArray<T>(
+  array: T[],
+  predicate: (value: T, index: number, array: T[]) => unknown,
+  thisArg?: unknown,
+): [matches: T[], nonMatches: T[]];
+
+/**
+ * Split an array into a pair of arrays based on a conditional function.
+ * @param array - The array to split into 2.
+ * @param predicate - A function accepting up to 3 arguments. The split function calls the function once per element of the array.
+ * @param thisArg -  An object to which the this keyword can refer in the predicate function. If thisArg is omitted, `undefined` is used as the this value.
+ * @returns A pair of shallowly-copied arrays containing every element for which `predicate` did or did not return a value coercible to the boolean `true`.
+ */
+export function splitArray<T>(
+  array: T[],
+  predicate: (value: T, index: number, array: T[]) => unknown,
+  thisArg?: any,
+): [matches: T[], nonMatches: T[]] {
+  const matches: T[] = [];
+  const nonMatches: T[] = [];
+
+  const p = predicate.bind(thisArg) as typeof predicate;
+  array.forEach((val, index, ar) => {
+    if (p(val, index, ar)) {
+      matches.push(val);
+    } else {
+      nonMatches.push(val);
+    }
+  });
+  return [matches, nonMatches];
+}

test/abilities/wimp_out.test.ts

@@ -8,11 +8,12 @@ import { ArenaTagType } from "#enums/arena-tag-type";
 import { BattlerTagType } from "#enums/battler-tag-type";
 import { Moves } from "#enums/moves";
 import { Species } from "#enums/species";
-import { Stat } from "#enums/stat";
 import { StatusEffect } from "#enums/status-effect";
-import { WeatherType } from "#enums/weather-type";
 import Phaser from "phaser";
 import { afterEach, beforeAll, beforeEach, describe, expect, it, vi } from "vitest";
+import { BattleType } from "#enums/battle-type";
+import { HitResult } from "#app/field/pokemon";
+import type { ModifierOverride } from "#app/modifier/modifier-type";
 
 describe("Abilities - Wimp Out", () => {
   let phaserGame: Phaser.Game;
@@ -37,7 +38,7 @@ describe("Abilities - Wimp Out", () => {
       .enemyPassiveAbility(Abilities.NO_GUARD)
       .startingLevel(90)
       .enemyLevel(70)
-      .moveset([Moves.SPLASH, Moves.FALSE_SWIPE, Moves.ENDURE, Moves.THUNDER_PUNCH])
+      .moveset([Moves.SPLASH, Moves.FALSE_SWIPE, Moves.ENDURE, Moves.GUILLOTINE])
       .enemyMoveset(Moves.FALSE_SWIPE)
       .disableCrits();
   });
@@ -72,16 +73,17 @@ describe("Abilities - Wimp Out", () => {
     const wimpod = game.scene.getPlayerPokemon()!;
     wimpod.hp *= 0.52;
 
-    game.move.select(Moves.THUNDER_PUNCH);
+    game.move.select(Moves.SPLASH);
     game.doSelectPartyPokemon(1);
     await game.phaseInterceptor.to("TurnEndPhase");
 
-    // Wimpod switched out after taking a hit, canceling its upcoming MovePhase before it could attack
+    // Wimpod switched out after taking a hit, canceling its upcoming MoveEffectPhase before it could attack
     confirmSwitch();
     expect(game.scene.getEnemyPokemon()!.getInverseHp()).toBe(0);
     expect(game.phaseInterceptor.log.reduce((count, phase) => count + (phase === "MoveEffectPhase" ? 1 : 0), 0)).toBe(
       1,
     );
+    expect(wimpod.turnData.acted).toBe(false);
   });
 
   it("should not trigger if user faints from damage", async () => {
@@ -91,12 +93,12 @@ describe("Abilities - Wimp Out", () => {
     const wimpod = game.scene.getPlayerPokemon()!;
     wimpod.hp *= 0.52;
 
-    game.move.select(Moves.THUNDER_PUNCH);
+    game.move.select(Moves.SPLASH);
     game.doSelectPartyPokemon(1);
     await game.phaseInterceptor.to("TurnEndPhase");
 
     expect(wimpod.isFainted()).toBe(true);
-    confirmNoSwitch();
+    expect(wimpod.waveData.abilitiesApplied).not.toContain(Abilities.WIMP_OUT);
   });
 
   it("should trigger regenerator passive when switching out", async () => {
@@ -128,15 +130,15 @@ describe("Abilities - Wimp Out", () => {
     expect(!isVisible && hasFled).toBe(true);
   });
 
-  it("should not trigger when HP already below half", async () => {
+  it("should not trigger if HP already below half", async () => {
     await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
     const wimpod = game.scene.getPlayerPokemon()!;
-    wimpod.hp = 5;
+    wimpod.hp *= 0.1;
 
     game.move.select(Moves.SPLASH);
     await game.phaseInterceptor.to("TurnEndPhase");
 
-    expect(wimpod.hp).toEqual(1);
+    expect(wimpod.getHpRatio()).toBeLessThan(0.1);
     confirmNoSwitch();
   });
 
@@ -155,8 +157,35 @@ describe("Abilities - Wimp Out", () => {
     confirmSwitch();
   });
 
+  // TODO: Enable when dynamic speed order happens
+  it.todo("should trigger separately for each Pokemon hit in speed order", async () => {
+    game.override.battleStyle("double").enemyLevel(600).enemyMoveset(Moves.DRAGON_ENERGY);
+    await game.classicMode.startBattle([Species.WIMPOD, Species.GOLISOPOD, Species.TYRANITAR, Species.KINGAMBIT]);
+
+    // Golisopod switches out, Wimpod switches back in immediately afterwards
+    game.move.select(Moves.ENDURE, BattlerIndex.PLAYER);
+    game.move.select(Moves.ENDURE, BattlerIndex.PLAYER_2);
+    game.doSelectPartyPokemon(3);
+    game.doSelectPartyPokemon(3);
+    await game.phaseInterceptor.to("TurnEndPhase");
+
+    expect(game.scene.getPlayerParty().map(p => p.species.speciesId)).toBe([
+      Species.TYRANITAR,
+      Species.WIMPOD,
+      Species.KINGAMBIT,
+      Species.GOLISOPOD,
+    ]);
+
+    // Ttar and Kingambit should be at full HP; wimpod and golisopod should not
+    // Ttar and Wimpod should be on field; kingambit and golisopod should not
+    game.scene.getPlayerParty().forEach((p, i) => {
+      expect(p.isOnField()).toBe(i < 2);
+      expect(p.isFullHp()).toBe(i % 2 === 1);
+    });
+  });
+
   it("should block U-turn or Volt Switch on activation", async () => {
-    game.override.startingLevel(95).enemyMoveset([Moves.U_TURN]);
+    game.override.enemyMoveset(Moves.U_TURN);
     await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
 
     game.move.select(Moves.SPLASH);
@@ -170,12 +199,20 @@ describe("Abilities - Wimp Out", () => {
   });
 
   it("should not block U-turn or Volt Switch if not activated", async () => {
-    game.override.startingLevel(190).startingWave(8).enemyMoveset([Moves.U_TURN]);
+    game.override.enemyMoveset(Moves.U_TURN).battleType(BattleType.TRAINER);
     await game.classicMode.startBattle([Species.GOLISOPOD, Species.TYRUNT]);
-    const RIVAL_NINJASK1 = game.scene.getEnemyPokemon()?.id;
+    const ninjask1 = game.scene.getEnemyPokemon()!;
+
+    vi.spyOn(game.scene.getPlayerPokemon()!, "getAttackDamage").mockReturnValue({
+      cancelled: false,
+      damage: 1,
+      result: HitResult.EFFECTIVE,
+    });
+
     game.move.select(Moves.SPLASH);
-    await game.phaseInterceptor.to("BerryPhase", false);
+    await game.phaseInterceptor.to("TurnEndPhase");
-    expect(game.scene.getEnemyPokemon()?.id !== RIVAL_NINJASK1);
+
+    expect(ninjask1.isOnField()).toBe(true);
   });
 
   it("should not activate from Dragon Tail and Circle Throw", async () => {
@@ -185,7 +222,6 @@ describe("Abilities - Wimp Out", () => {
     const wimpod = game.scene.getPlayerPokemon()!;
 
     game.move.select(Moves.SPLASH);
-    game.doSelectPartyPokemon(1);
     await game.phaseInterceptor.to("SwitchSummonPhase", false);
 
     expect(wimpod.waveData.abilitiesApplied).not.toContain(Abilities.WIMP_OUT);
@@ -193,42 +229,78 @@ describe("Abilities - Wimp Out", () => {
     await game.phaseInterceptor.to("TurnEndPhase");
 
     expect(game.scene.getPlayerPokemon()!.species.speciesId).not.toBe(Species.WIMPOD);
+    // Force switches directly call `SwitchSummonPhase` to send in a random opponent,
+    // as opposed to `SwitchPhase` which allows for player choice
+    expect(game.phaseInterceptor.log).not.toContain("SwitchPhase");
   });
 
-  it.each<{ type: string; enemyMove?: Moves; enemyAbility?: Abilities }>([
+  it.each<{ type: string; playerMove?: Moves; playerPassive?: Abilities; enemyMove?: Moves; enemyAbility?: Abilities }>(
-    { type: "weather", enemyMove: Moves.HAIL },
+    [
-    { type: "status", enemyMove: Moves.TOXIC },
+      { type: "variable recoil moves", playerMove: Moves.HEAD_SMASH },
-    { type: "Curse", enemyMove: Moves.CURSE },
+      { type: "HP-based recoil moves", playerMove: Moves.CHLOROBLAST },
-    { type: "Salt Cure", enemyMove: Moves.SALT_CURE },
+      { type: "weather", enemyMove: Moves.HAIL },
-    { type: "partial trapping moves", enemyMove: Moves.WHIRLPOOL },
+      { type: "status", enemyMove: Moves.TOXIC },
-    { type: "Leech Seed", enemyMove: Moves.LEECH_SEED },
+      { type: "Ghost-type Curse", enemyMove: Moves.CURSE },
-    { type: "Nightmare", enemyMove: Moves.NIGHTMARE },
+      { type: "Salt Cure", enemyMove: Moves.SALT_CURE },
-    { type: "Aftermath", enemyAbility: Abilities.AFTERMATH },
+      { type: "partial trapping moves", enemyMove: Moves.WHIRLPOOL }, // no guard passive makes this guaranteed
-    { type: "Bad Dreams", enemyAbility: Abilities.BAD_DREAMS },
+      { type: "Leech Seed", enemyMove: Moves.LEECH_SEED },
-  ])(
+      { type: "Powder", playerMove: Moves.EMBER, enemyMove: Moves.POWDER },
-    "should activate from damage caused by $name",
+      { type: "Nightmare", playerPassive: Abilities.COMATOSE, enemyMove: Moves.NIGHTMARE },
-    async ({ enemyMove = Moves.SPLASH, enemyAbility = Abilities.BALL_FETCH }) => {
+      { type: "Bad Dreams", playerPassive: Abilities.COMATOSE, enemyAbility: Abilities.BAD_DREAMS },
+    ],
+  )(
+    "should activate from damage caused by $type",
+    async ({
+      playerMove = Moves.SPLASH,
+      playerPassive = Abilities.NONE,
+      enemyMove = Moves.SPLASH,
+      enemyAbility = Abilities.BALL_FETCH,
+    }) => {
       game.override
-        .passiveAbility(Abilities.COMATOSE)
+        .moveset(playerMove)
+        .passiveAbility(playerPassive)
         .enemySpecies(Species.GASTLY)
         .enemyMoveset(enemyMove)
-        .enemyAbility(enemyAbility)
+        .enemyAbility(enemyAbility);
-        .enemyLevel(1);
       await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
 
       const wimpod = game.scene.getPlayerPokemon()!;
       expect(wimpod).toBeDefined();
-      wimpod.hp *= 0.55;
+      wimpod.hp = toDmgValue(wimpod.getMaxHp() / 2 + 5);
+      // mock enemy attack damage func to only do 1 dmg (for whirlpool)
+      vi.spyOn(wimpod, "getAttackDamage").mockReturnValueOnce({
+        cancelled: false,
+        result: HitResult.EFFECTIVE,
+        damage: 1,
+      });
 
-      game.move.select(Moves.THUNDER_PUNCH);
+      game.move.select(playerMove);
       game.doSelectPartyPokemon(1);
-      await game.setTurnOrder([BattlerIndex.ENEMY, BattlerIndex.PLAYER]);
+      await game.toNextTurn();
-      await game.phaseInterceptor.to("TurnEndPhase");
 
       confirmSwitch();
     },
   );
 
+  it.each<[name: string, ability: Abilities]>([
+    ["Innards Out", Abilities.INNARDS_OUT],
+    ["Aftermath", Abilities.AFTERMATH],
+    ["Rough Skin", Abilities.ROUGH_SKIN],
+  ])("should trigger after taking damage from %s ability", async (_, ability) => {
+    game.override.enemyAbility(ability).enemyMoveset(Moves.SPLASH);
+    await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
+
+    const wimpod = game.scene.getPlayerPokemon()!;
+    wimpod.hp *= 0.51;
+    game.scene.getEnemyPokemon()!.hp = wimpod.hp - 1; // Ensure innards out doesn't KO
+
+    game.move.select(Moves.GUILLOTINE);
+    game.doSelectPartyPokemon(1);
+    await game.toNextWave();
+
+    confirmSwitch();
+  });
+
   it("should not trigger from Sheer Force-boosted moves", async () => {
     game.override.enemyAbility(Abilities.SHEER_FORCE).enemyMoveset(Moves.SLUDGE_BOMB).startingLevel(95);
     await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
@@ -241,18 +313,7 @@ describe("Abilities - Wimp Out", () => {
     confirmNoSwitch();
   });
 
-  it("should trigger from recoil damage", async () => {
+  it("should trigger from Flame Burst splash damage in doubles", async () => {
-    game.override.moveset(Moves.HEAD_SMASH).enemyMoveset(Moves.SPLASH);
-    await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
-
-    game.move.select(Moves.HEAD_SMASH);
-    game.doSelectPartyPokemon(1);
-    await game.phaseInterceptor.to("TurnEndPhase");
-
-    confirmSwitch();
-  });
-
-  it("should trigger from Flame Burst ally damage in doubles", async () => {
     game.override.battleStyle("double").enemyMoveset([Moves.FLAME_BURST, Moves.SPLASH]);
     await game.classicMode.startBattle([Species.WIMPOD, Species.ZYGARDE, Species.TYRUNT]);
 
@@ -267,20 +328,36 @@ describe("Abilities - Wimp Out", () => {
     game.doSelectPartyPokemon(2);
     await game.phaseInterceptor.to("TurnEndPhase");
 
-    confirmSwitch();
+    expect(wimpod.isOnField()).toBe(false);
+    expect(wimpod.getHpRatio()).toBeLessThan(0.5);
   });
 
-  it("should not activate when the Pokémon cuts its own HP", async () => {
+  it("should not activate when the Pokémon cuts its own HP below half", async () => {
-    game.override.moveset(Moves.SUBSTITUTE).enemyMoveset(Moves.SPLASH);
+    game.override.moveset(Moves.SUBSTITUTE).enemyMoveset([Moves.TIDY_UP, Moves.ROUND]);
     await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
 
+    // Turn 1: Substitute knocks below half; no switch
     const wimpod = game.scene.getPlayerPokemon()!;
     wimpod.hp *= 0.52;
 
     game.move.select(Moves.SUBSTITUTE);
-    await game.phaseInterceptor.to("TurnEndPhase");
+    await game.forceEnemyMove(Moves.TIDY_UP);
+    game.doSelectPartyPokemon(1);
+    await game.setTurnOrder([BattlerIndex.PLAYER, BattlerIndex.ENEMY]);
+    await game.toNextTurn();
 
     confirmNoSwitch();
+
+    // Turn 2: get back enough HP that substitute doesn't put us under
+    wimpod.hp = wimpod.getMaxHp() * 0.8;
+
+    game.move.select(Moves.SUBSTITUTE);
+    game.doSelectPartyPokemon(1);
+    await game.forceEnemyMove(Moves.ROUND);
+    await game.setTurnOrder([BattlerIndex.PLAYER, BattlerIndex.ENEMY]);
+    await game.phaseInterceptor.to("TurnEndPhase");
+
+    confirmSwitch();
   });
 
   it("should not trigger when neutralized", async () => {
@@ -295,9 +372,9 @@ describe("Abilities - Wimp Out", () => {
 
   it("should disregard Shell Bell recovery while still activating it before switching", async () => {
     game.override
-      .moveset([Moves.DOUBLE_EDGE])
+      .moveset(Moves.DOUBLE_EDGE)
       .enemyMoveset([Moves.SPLASH])
-      .startingHeldItems([{ name: "SHELL_BELL", count: 4 }]);
+      .startingHeldItems([{ name: "SHELL_BELL", count: 4 }]); // heals 50% of damage dealt, more than recoil takes away
     await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
 
     const wimpod = game.scene.getPlayerPokemon()!;
@@ -307,29 +384,34 @@ describe("Abilities - Wimp Out", () => {
     game.doSelectPartyPokemon(1);
     await game.phaseInterceptor.to("TurnEndPhase");
 
-    expect(game.scene.getPlayerParty()[1]).toBe(wimpod);
+    // Wimp out activated before shell bell healing
-    expect(wimpod.hp).toBeGreaterThan(toDmgValue(wimpod.getMaxHp() / 2));
+    expect(wimpod.getHpRatio()).toBeGreaterThan(0.5);
-    expect(game.phaseInterceptor.log).toContain("SwitchSummonPhase");
+    confirmSwitch();
-    expect(game.scene.getPlayerPokemon()!.species.speciesId).toBe(Species.TYRUNT);
+    expect(game.phaseInterceptor.log).toContain("PokemonHealPhase");
+  });
+
+  it("should activate from entry hazard damage", async () => {
+    game.scene.arena.addTag(ArenaTagType.STEALTH_ROCK, 1, Moves.STEALTH_ROCK, 0, ArenaTagSide.ENEMY);
+    game.scene.arena.addTag(ArenaTagType.SPIKES, 1, Moves.SPIKES, 0, ArenaTagSide.ENEMY);
+    game.override.enemySpecies(Species.CENTISKORCH).enemyAbility(Abilities.WIMP_OUT);
+    await game.classicMode.startBattle([Species.TYRUNT]);
+
+    expect(game.phaseInterceptor.log).not.toContain("MovePhase");
+    expect(game.phaseInterceptor.log).toContain("BattleEndPhase");
   });
 
   it("should not switch if Magic Guard prevents damage", async () => {
-    game.scene.arena.addTag(ArenaTagType.STEALTH_ROCK, 1, Moves.STEALTH_ROCK, 0, ArenaTagSide.ENEMY);
+    game.override.passiveAbility(Abilities.MAGIC_GUARD).enemyMoveset(Moves.LEECH_SEED);
-    game.scene.arena.addTag(ArenaTagType.SPIKES, 1, Moves.SPIKES, 0, ArenaTagSide.ENEMY);
-    game.override
-      .passiveAbility(Abilities.MAGIC_GUARD)
-      .enemyMoveset([Moves.LEECH_SEED])
-      .weather(WeatherType.HAIL)
-      .statusEffect(StatusEffect.POISON);
     await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
-    game.scene.getPlayerPokemon()!.hp *= 0.51;
+
+    const wimpod = game.scene.getPlayerPokemon()!;
+    wimpod.hp *= 0.51;
 
     game.move.select(Moves.SPLASH);
-    await game.phaseInterceptor.to("TurnEndPhase");
+    await game.toNextTurn();
 
-    expect(game.scene.getPlayerParty()[0].getHpRatio()).toEqual(0.51);
+    confirmNoSwitch();
-    expect(game.phaseInterceptor.log).not.toContain("SwitchSummonPhase");
+    expect(wimpod.getHpRatio()).toBeCloseTo(0.51);
-    expect(game.scene.getPlayerPokemon()!.species.speciesId).toBe(Species.WIMPOD);
   });
 
   it("should not cancel a double battle on activation", async () => {
@@ -352,17 +434,7 @@ describe("Abilities - Wimp Out", () => {
     expect(enemySecPokemon.hp).toEqual(enemySecPokemon.getMaxHp());
   });
 
-  it("should activate from entry hazard damage", async () => {
+  it("triggers move effects on the wimp out user before switching", async () => {
-    game.scene.arena.addTag(ArenaTagType.STEALTH_ROCK, 1, Moves.STEALTH_ROCK, 0, ArenaTagSide.ENEMY);
-    game.scene.arena.addTag(ArenaTagType.SPIKES, 1, Moves.SPIKES, 0, ArenaTagSide.ENEMY);
-    game.override.enemySpecies(Species.CENTISKORCH).enemyAbility(Abilities.WIMP_OUT).startingWave(4);
-    await game.classicMode.startBattle([Species.TYRUNT]);
-
-    expect(game.phaseInterceptor.log).not.toContain("MovePhase");
-    expect(game.phaseInterceptor.log).toContain("BattleEndPhase");
-  });
-
-  it("triggers status on the wimp out user before a new pokemon is switched in", async () => {
     game.override.enemyMoveset(Moves.SLUDGE_BOMB).startingLevel(80);
     await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
     vi.spyOn(allMoves[Moves.SLUDGE_BOMB], "chance", "get").mockReturnValue(100);
@@ -371,92 +443,64 @@ describe("Abilities - Wimp Out", () => {
     game.doSelectPartyPokemon(1);
     await game.phaseInterceptor.to("TurnEndPhase");
 
-    expect(game.scene.getPlayerParty()[1].status?.effect).toEqual(StatusEffect.POISON);
     confirmSwitch();
+    expect(game.scene.getPlayerParty()[1].status?.effect).toBe(StatusEffect.POISON);
   });
 
-  it("triggers after last hit of multi hit moves", async () => {
+  it.each<{ type: string; move?: Moves; ability?: Abilities; items?: ModifierOverride[] }>([
-    game.override.enemyMoveset(Moves.BULLET_SEED).enemyAbility(Abilities.SKILL_LINK);
+    { type: "normal", move: Moves.DUAL_CHOP },
-    await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
+    { type: "Parental Bond", ability: Abilities.PARENTAL_BOND },
+    { type: "Multi Lens", items: [{ name: "MULTI_LENS", count: 1 }] },
+  ])(
+    "should trigger after the last hit of $type multi-strike moves",
+    async ({ move = Moves.TACKLE, ability = Abilities.COMPOUND_EYES, items = [] }) => {
+      game.override.enemyMoveset(move).enemyAbility(ability).enemyHeldItems(items);
+      await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
 
-    game.scene.getPlayerPokemon()!.hp *= 0.51;
+      const wimpod = game.scene.getPlayerPokemon()!;
+      wimpod.hp *= 0.51;
 
-    game.move.select(Moves.ENDURE);
+      game.move.select(Moves.ENDURE);
-    game.doSelectPartyPokemon(1);
+      game.doSelectPartyPokemon(1);
-    await game.phaseInterceptor.to("TurnEndPhase");
-
-    const enemyPokemon = game.scene.getEnemyPokemon()!;
-    expect(enemyPokemon.turnData.hitsLeft).toBe(0);
-    expect(enemyPokemon.turnData.hitCount).toBe(5);
-    confirmSwitch();
-  });
-
-  it("triggers after last hit of multi hit moves from multi lens", async () => {
-    game.override.enemyMoveset(Moves.TACKLE).enemyHeldItems([{ name: "MULTI_LENS", count: 1 }]);
-    await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
-
-    game.scene.getPlayerPokemon()!.hp *= 0.51;
-
-    game.move.select(Moves.ENDURE);
-    game.doSelectPartyPokemon(1);
-    await game.phaseInterceptor.to("TurnEndPhase");
-
-    const enemyPokemon = game.scene.getEnemyPokemon()!;
-    expect(enemyPokemon.turnData.hitsLeft).toBe(0);
-    expect(enemyPokemon.turnData.hitCount).toBe(2);
-    confirmSwitch();
-  });
-
-  it("triggers after last hit of Parental Bond", async () => {
-    game.override.enemyMoveset(Moves.TACKLE).enemyAbility(Abilities.PARENTAL_BOND);
-    await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
-
-    game.scene.getPlayerPokemon()!.hp *= 0.51;
-
-    game.move.select(Moves.ENDURE);
-    game.doSelectPartyPokemon(1);
-    await game.phaseInterceptor.to("TurnEndPhase");
-
-    const enemyPokemon = game.scene.getEnemyPokemon()!;
-    expect(enemyPokemon.turnData.hitsLeft).toBe(0);
-    expect(enemyPokemon.turnData.hitCount).toBe(2);
-    confirmSwitch();
-  });
-
-  // TODO: This interaction is not implemented yet
-  it.todo("should not activate if the Pokémon's HP falls below half due to hurting itself in confusion", async () => {
-    game.override.moveset([Moves.SWORDS_DANCE]).enemyMoveset([Moves.SWAGGER]);
-    await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
-    const playerPokemon = game.scene.getPlayerPokemon()!;
-    playerPokemon.hp *= 0.51;
-    playerPokemon.setStatStage(Stat.ATK, 6);
-    playerPokemon.addTag(BattlerTagType.CONFUSED);
-
-    // TODO: add helper function to force confusion self-hits
-
-    while (playerPokemon.getHpRatio() > 0.49) {
-      game.move.select(Moves.SWORDS_DANCE);
       await game.phaseInterceptor.to("TurnEndPhase");
-    }
+
+      const enemyPokemon = game.scene.getEnemyPokemon()!;
+      expect(enemyPokemon.turnData.hitsLeft).toBe(0);
+      expect(enemyPokemon.turnData.hitCount).toBe(2);
+      confirmSwitch();
+
+      // Switch triggered after the MEPs for both hits finished
+      const phaseLogs = game.phaseInterceptor.log;
+      expect(phaseLogs.filter(l => l === "MoveEffectPhase")).toHaveLength(3); // 1 for endure + 2 for dual hit
+      expect(phaseLogs.lastIndexOf("SwitchSummonPhase")).toBeGreaterThan(phaseLogs.lastIndexOf("MoveEffectPhase"));
+    },
+  );
+
+  it("should not activate from confusion damage", async () => {
+    game.override.enemyMoveset(Moves.CONFUSE_RAY).confusionActivation(true);
+    await game.classicMode.startBattle([Species.WIMPOD, Species.TYRUNT]);
+
+    const wimpod = game.scene.getPlayerPokemon()!;
+    wimpod.hp *= 0.51;
+
+    game.move.select(Moves.SPLASH);
+    await game.setTurnOrder([BattlerIndex.ENEMY, BattlerIndex.PLAYER]);
+    await game.phaseInterceptor.to("TurnEndPhase");
 
     confirmNoSwitch();
   });
 
   it("should not activate on wave X0 bosses", async () => {
-    game.override.enemyAbility(Abilities.WIMP_OUT).startingLevel(5850).startingWave(10);
+    game.override.enemyAbility(Abilities.WIMP_OUT).startingLevel(5850).startingWave(10).enemyHealthSegments(3);
     await game.classicMode.startBattle([Species.GOLISOPOD]);
 
     const enemyPokemon = game.scene.getEnemyPokemon()!;
 
-    // Use 2 turns of False Swipe due to opponent's health bar shield
-    game.move.select(Moves.FALSE_SWIPE);
-    await game.toNextTurn();
     game.move.select(Moves.FALSE_SWIPE);
     await game.toNextTurn();
 
-    const isVisible = enemyPokemon.visible;
+    expect(enemyPokemon.visible).toBe(true);
-    const hasFled = enemyPokemon.switchOutStatus;
+    expect(enemyPokemon.switchOutStatus).toBe(false);
-    expect(isVisible && !hasFled).toBe(true);
   });
 
   it("should not skip battles when triggered in a double battle", async () => {

test/items/reviver_seed.test.ts

@@ -106,9 +106,10 @@ describe("Items - Reviver Seed", () => {
 
   // Self-damage tests
   it.each([
-    { moveType: "Recoil", move: Moves.DOUBLE_EDGE },
+    { moveType: "Relative Recoil", move: Moves.DOUBLE_EDGE },
+    { moveType: "HP% Recoil", move: Moves.CHLOROBLAST },
     { moveType: "Self-KO", move: Moves.EXPLOSION },
-    { moveType: "Self-Deduction", move: Moves.CURSE },
+    { moveType: "Ghost-type Curse", move: Moves.CURSE },
     { moveType: "Liquid Ooze", move: Moves.GIGA_DRAIN },
   ])("should not activate the holder's reviver seed from $moveType", async ({ move }) => {
     game.override

test/moves/dragon_tail.test.ts

@@ -1,8 +1,6 @@
 import { BattlerIndex } from "#app/battle";
 import { allMoves } from "#app/data/moves/move";
-import { Status } from "#app/data/status-effect";
 import { Challenges } from "#enums/challenges";
-import { StatusEffect } from "#enums/status-effect";
 import { PokemonType } from "#enums/pokemon-type";
 import { Abilities } from "#enums/abilities";
 import { Moves } from "#enums/moves";
@@ -10,6 +8,11 @@ import { Species } from "#enums/species";
 import GameManager from "#test/testUtils/gameManager";
 import Phaser from "phaser";
 import { afterEach, beforeAll, beforeEach, describe, expect, it, vi } from "vitest";
+import { BattleType } from "#enums/battle-type";
+import { TrainerSlot } from "#enums/trainer-slot";
+import { TrainerType } from "#enums/trainer-type";
+import { splitArray } from "#app/utils/common";
+import { BattlerTagType } from "#enums/battler-tag-type";
 
 describe("Moves - Dragon Tail", () => {
   let phaserGame: Phaser.Game;
@@ -38,23 +41,6 @@ describe("Moves - Dragon Tail", () => {
     vi.spyOn(allMoves[Moves.DRAGON_TAIL], "accuracy", "get").mockReturnValue(100);
   });
 
-  it("should cause opponent to flee, and not crash", async () => {
-    await game.classicMode.startBattle([Species.DRATINI]);
-
-    const enemyPokemon = game.scene.getEnemyPokemon()!;
-
-    game.move.select(Moves.DRAGON_TAIL);
-
-    await game.phaseInterceptor.to("BerryPhase");
-
-    const isVisible = enemyPokemon.visible;
-    const hasFled = enemyPokemon.switchOutStatus;
-    expect(!isVisible && hasFled).toBe(true);
-
-    // simply want to test that the game makes it this far without crashing
-    await game.phaseInterceptor.to("BattleEndPhase");
-  });
-
   it("should cause opponent to flee, display ability, and not crash", async () => {
     game.override.enemyAbility(Abilities.ROUGH_SKIN);
     await game.classicMode.startBattle([Species.DRATINI]);
@@ -68,7 +54,8 @@ describe("Moves - Dragon Tail", () => {
 
     const isVisible = enemyPokemon.visible;
     const hasFled = enemyPokemon.switchOutStatus;
-    expect(!isVisible && hasFled).toBe(true);
+    expect(isVisible).toBe(false);
+    expect(hasFled).toBe(true);
     expect(leadPokemon.hp).toBeLessThan(leadPokemon.getMaxHp());
   });
 
@@ -101,6 +88,47 @@ describe("Moves - Dragon Tail", () => {
     expect(enemySecPokemon.hp).toBeLessThan(enemySecPokemon.getMaxHp());
   });
 
+  it("should force trainers to switch randomly without selecting from a partner's party", async () => {
+    game.override
+      .battleStyle("double")
+      .enemyMoveset(Moves.SPLASH)
+      .enemyAbility(Abilities.STURDY)
+      .battleType(BattleType.TRAINER)
+      .randomTrainer({ trainerType: TrainerType.TATE, alwaysDouble: true })
+      .enemySpecies(0);
+    await game.classicMode.startBattle([Species.WIMPOD, Species.TYRANITAR]);
+
+    // Grab each trainer's pokemon based on species name
+    const [tateParty, lizaParty] = splitArray(
+      game.scene.getEnemyParty(),
+      pkmn => pkmn.trainerSlot === TrainerSlot.TRAINER,
+    ).map(a => a.map(p => p.species.name));
+
+    expect(tateParty).not.toEqual(lizaParty);
+
+    // Force enemy trainers to switch to the first mon available.
+    // Due to how enemy trainer parties are laid out, this prevents false positives
+    // as Tate's pokemon are placed immediately before Liza's corresponding members.
+    vi.fn(Phaser.Math.RND.integerInRange).mockImplementation(min => min);
+
+    // Spy on the function responsible for making informed switches
+    const choiceSwitchSpy = vi.spyOn(game.scene.currentBattle.trainer!, "getNextSummonIndex");
+
+    game.move.select(Moves.DRAGON_TAIL, BattlerIndex.PLAYER, BattlerIndex.ENEMY_2);
+    game.move.select(Moves.SPLASH, BattlerIndex.PLAYER_2);
+    await game.phaseInterceptor.to("BerryPhase");
+
+    const [tatePartyNew, lizaPartyNew] = splitArray(
+      game.scene.getEnemyParty(),
+      pkmn => pkmn.trainerSlot === TrainerSlot.TRAINER,
+    ).map(a => a.map(p => p.species.name));
+
+    // Forced switch move should have switched Liza's Pokemon with another one of her own at random
+    expect(tatePartyNew).toEqual(tateParty);
+    expect(lizaPartyNew).not.toEqual(lizaParty);
+    expect(choiceSwitchSpy).not.toHaveBeenCalled();
+  });
+
   it("should redirect targets upon opponent flee", async () => {
     game.override.battleStyle("double").enemyMoveset(Moves.SPLASH).enemyAbility(Abilities.ROUGH_SKIN);
     await game.classicMode.startBattle([Species.DRATINI, Species.DRATINI, Species.WAILORD, Species.WAILORD]);
@@ -128,7 +156,7 @@ describe("Moves - Dragon Tail", () => {
     expect(enemySecPokemon.hp).toBeLessThan(enemySecPokemon.getMaxHp());
   });
 
-  it("doesn't switch out if the target has suction cups", async () => {
+  it("should not switch out a target with suction cups", async () => {
     game.override.enemyAbility(Abilities.SUCTION_CUPS);
     await game.classicMode.startBattle([Species.REGIELEKI]);
 
@@ -137,9 +165,25 @@ describe("Moves - Dragon Tail", () => {
     game.move.select(Moves.DRAGON_TAIL);
     await game.phaseInterceptor.to("TurnEndPhase");
 
+    expect(enemy.isOnField()).toBe(true);
     expect(enemy.isFullHp()).toBe(false);
   });
 
+  it("should not switch out a Commanded Dondozo", async () => {
+    game.override.battleStyle("double").enemySpecies(Species.DONDOZO);
+    await game.classicMode.startBattle([Species.REGIELEKI]);
+
+    // pretend dondozo 2 commanded dondozo 1 (silly I know, but it works)
+    const [dondozo1, dondozo2] = game.scene.getEnemyField();
+    dondozo1.addTag(BattlerTagType.COMMANDED, 1, Moves.NONE, dondozo2.id);
+
+    game.move.select(Moves.DRAGON_TAIL);
+    await game.phaseInterceptor.to("TurnEndPhase");
+
+    expect(dondozo1.isOnField()).toBe(true);
+    expect(dondozo1.isFullHp()).toBe(false);
+  });
+
   it("should force a switch upon fainting an opponent normally", async () => {
     game.override.startingWave(5).startingLevel(1000); // To make sure Dragon Tail KO's the opponent
     await game.classicMode.startBattle([Species.DRATINI]);
@@ -227,81 +271,55 @@ describe("Moves - Dragon Tail", () => {
     expect(charmander.getInverseHp()).toBeGreaterThan(0);
   });
 
-  it("should not force a switch to a challenge-ineligible Pokemon", async () => {
+  it("should not force a switch to a fainted or challenge-ineligible Pokemon", async () => {
     game.override.enemyMoveset(Moves.DRAGON_TAIL).startingLevel(100).enemyLevel(1);
     // Mono-Water challenge, Eevee is ineligible
     game.challengeMode.addChallenge(Challenges.SINGLE_TYPE, PokemonType.WATER + 1, 0);
     await game.challengeMode.startBattle([Species.LAPRAS, Species.EEVEE, Species.TOXAPEX, Species.PRIMARINA]);
 
     const [lapras, eevee, toxapex, primarina] = game.scene.getPlayerParty();
+    expect(toxapex).toBeDefined();
 
-    // Turn 1: Mock an RNG call that would normally call for switching to Eevee, but it is ineligible
+    // Mock an RNG call to switch to the first eligible pokemon.
+    // Eevee is ineligible and Toxapex is fainted, so it should proc on Primarina instead
     vi.spyOn(game.scene, "randBattleSeedInt").mockImplementation((_range, min = 0) => {
       return min;
     });
     game.move.select(Moves.SPLASH);
+    await game.killPokemon(toxapex);
     await game.toNextTurn();
 
     expect(lapras.isOnField()).toBe(false);
     expect(eevee.isOnField()).toBe(false);
-    expect(toxapex.isOnField()).toBe(true);
+    expect(toxapex.isOnField()).toBe(false);
-    expect(primarina.isOnField()).toBe(false);
+    expect(primarina.isOnField()).toBe(true);
     expect(lapras.getInverseHp()).toBeGreaterThan(0);
   });
 
-  it("should not force a switch to a fainted Pokemon", async () => {
+  it("should deal damage without switching if there are no available backup Pokemon to switch into", async () => {
-    game.override.enemyMoveset([Moves.SPLASH, Moves.DRAGON_TAIL]).startingLevel(100).enemyLevel(1);
+    game.override.enemyMoveset(Moves.DRAGON_TAIL).battleStyle("double").startingLevel(100).enemyLevel(1);
-    await game.classicMode.startBattle([Species.LAPRAS, Species.EEVEE, Species.TOXAPEX, Species.PRIMARINA]);
+    // Mono-Water challenge
+    game.challengeMode.addChallenge(Challenges.SINGLE_TYPE, PokemonType.WATER + 1, 0);
+    await game.challengeMode.startBattle([Species.LAPRAS, Species.KYOGRE, Species.EEVEE, Species.CLOYSTER]);
 
-    const [lapras, eevee, toxapex, primarina] = game.scene.getPlayerParty();
+    const [lapras, kyogre, eevee, cloyster] = game.scene.getPlayerParty();
+    expect(cloyster).toBeDefined();
 
-    // Turn 1: Eevee faints
+    game.move.select(Moves.SPLASH, BattlerIndex.PLAYER);
-    eevee.hp = 0;
+    game.move.select(Moves.SPLASH, BattlerIndex.PLAYER_2);
-    eevee.status = new Status(StatusEffect.FAINT);
+    await game.forceEnemyMove(Moves.DRAGON_TAIL, BattlerIndex.PLAYER);
-    expect(eevee.isFainted()).toBe(true);
+    await game.forceEnemyMove(Moves.DRAGON_TAIL, BattlerIndex.PLAYER_2);
-    game.move.select(Moves.SPLASH);
+    await game.killPokemon(cloyster);
-    await game.forceEnemyMove(Moves.SPLASH);
-    await game.toNextTurn();
-
-    // Turn 2: Mock an RNG call that would normally call for switching to Eevee, but it is fainted
-    vi.spyOn(game.scene, "randBattleSeedInt").mockImplementation((_range, min = 0) => {
-      return min;
-    });
-    game.move.select(Moves.SPLASH);
-    await game.forceEnemyMove(Moves.DRAGON_TAIL);
-    await game.toNextTurn();
-
-    expect(lapras.isOnField()).toBe(false);
-    expect(eevee.isOnField()).toBe(false);
-    expect(toxapex.isOnField()).toBe(true);
-    expect(primarina.isOnField()).toBe(false);
-    expect(lapras.getInverseHp()).toBeGreaterThan(0);
-  });
-
-  it("should not force a switch if there are no available Pokemon to switch into", async () => {
-    game.override.enemyMoveset([Moves.SPLASH, Moves.DRAGON_TAIL]).startingLevel(100).enemyLevel(1);
-    await game.classicMode.startBattle([Species.LAPRAS, Species.EEVEE]);
-
-    const [lapras, eevee] = game.scene.getPlayerParty();
-
-    // Turn 1: Eevee faints
-    eevee.hp = 0;
-    eevee.status = new Status(StatusEffect.FAINT);
-    expect(eevee.isFainted()).toBe(true);
-    game.move.select(Moves.SPLASH);
-    await game.forceEnemyMove(Moves.SPLASH);
-    await game.toNextTurn();
-
-    // Turn 2: Mock an RNG call that would normally call for switching to Eevee, but it is fainted
-    vi.spyOn(game.scene, "randBattleSeedInt").mockImplementation((_range, min = 0) => {
-      return min;
-    });
-    game.move.select(Moves.SPLASH);
-    await game.forceEnemyMove(Moves.DRAGON_TAIL);
     await game.toNextTurn();
 
+    // Eevee is ineligble due to challenge and cloyster is fainted, leaving no backup pokemon able to switch in
     expect(lapras.isOnField()).toBe(true);
+    expect(kyogre.isOnField()).toBe(true);
     expect(eevee.isOnField()).toBe(false);
+    expect(cloyster.isOnField()).toBe(false);
     expect(lapras.getInverseHp()).toBeGreaterThan(0);
+    expect(kyogre.getInverseHp()).toBeGreaterThan(0);
+    expect(game.scene.getBackupPartyMemberIndices(true)).toHaveLength(0);
+    expect(game.phaseInterceptor.log).not.toContain("SwitchSummonPhase");
   });
 });

test/moves/powder.test.ts

@@ -7,9 +7,9 @@ import { Species } from "#enums/species";
 import { BerryPhase } from "#app/phases/berry-phase";
 import { MoveResult, PokemonMove } from "#app/field/pokemon";
 import { PokemonType } from "#enums/pokemon-type";
-import { MoveEffectPhase } from "#app/phases/move-effect-phase";
 import { StatusEffect } from "#enums/status-effect";
 import { BattlerIndex } from "#app/battle";
+import { toDmgValue } from "#app/utils/common";
 
 describe("Moves - Powder", () => {
   let phaserGame: Phaser.Game;
@@ -168,18 +168,13 @@ describe("Moves - Powder", () => {
     game.move.select(Moves.FIERY_DANCE, 0, BattlerIndex.ENEMY);
     game.move.select(Moves.POWDER, 1, BattlerIndex.ENEMY);
 
-    await game.phaseInterceptor.to(MoveEffectPhase);
+    await game.phaseInterceptor.to("BerryPhase", false);
-    const enemyStartingHp = enemyPokemon.hp;
-
-    await game.phaseInterceptor.to(BerryPhase, false);
 
     // player should not take damage
     expect(enemyPokemon.getLastXMoves()[0].result).toBe(MoveResult.FAIL);
     expect(playerPokemon.hp).toBe(playerPokemon.getMaxHp());
     // enemy should have taken damage from player's Fiery Dance + 2 Powder procs
-    expect(enemyPokemon.hp).toBe(
+    expect(enemyPokemon.hp).toBeLessThan(2 * toDmgValue(enemyPokemon.getMaxHp() / 4));
-      enemyStartingHp - playerPokemon.turnData.lastMoveDamageDealt - 2 * Math.floor(enemyPokemon.getMaxHp() / 4),
-    );
   });
 
   it("should cancel Fiery Dance, then prevent it from triggering Dancer", async () => {