Merge branch 'beta' into me-balance-changes

src/data/ability.ts

@@ -4342,6 +4342,30 @@ export class AlwaysHitAbAttr extends AbAttr { }
 /** Attribute for abilities that allow moves that make contact to ignore protection (i.e. Unseen Fist) */
 export class IgnoreProtectOnContactAbAttr extends AbAttr { }
 
+/**
+ * Attribute implementing the effects of {@link https://bulbapedia.bulbagarden.net/wiki/Infiltrator_(Ability) | Infiltrator}.
+ * Allows the source's moves to bypass the effects of opposing Light Screen, Reflect, Aurora Veil, Safeguard, Mist, and Substitute.
+ */
+export class InfiltratorAbAttr extends AbAttr {
+  /**
+   * Sets a flag to bypass screens, Substitute, Safeguard, and Mist
+   * @param pokemon n/a
+   * @param passive n/a
+   * @param simulated n/a
+   * @param cancelled n/a
+   * @param args `[0]` a {@linkcode Utils.BooleanHolder | BooleanHolder} containing the flag
+   * @returns `true` if the bypass flag was successfully set; `false` otherwise.
+   */
+  override apply(pokemon: Pokemon, passive: boolean, simulated: boolean, cancelled: null, args: any[]): boolean {
+    const bypassed = args[0];
+    if (args[0] instanceof Utils.BooleanHolder) {
+      bypassed.value = true;
+      return true;
+    }
+    return false;
+  }
+}
+
 export class UncopiableAbilityAbAttr extends AbAttr {
   constructor() {
     super(false);
@@ -5321,7 +5345,8 @@ export function initAbilities() {
       .attr(PostSummonTransformAbAttr)
       .attr(UncopiableAbilityAbAttr),
     new Ability(Abilities.INFILTRATOR, 5)
-      .unimplemented(),
+      .attr(InfiltratorAbAttr)
+      .partial(), // does not bypass Mist
     new Ability(Abilities.MUMMY, 5)
       .attr(PostDefendAbilityGiveAbAttr, Abilities.MUMMY)
       .bypassFaint(),

src/data/arena-tag.ts

@@ -7,7 +7,7 @@ import { getPokemonNameWithAffix } from "#app/messages";
 import Pokemon, { HitResult, PokemonMove } from "#app/field/pokemon";
 import { StatusEffect } from "#app/data/status-effect";
 import { BattlerIndex } from "#app/battle";
-import { BlockNonDirectDamageAbAttr, ChangeMovePriorityAbAttr, ProtectStatAbAttr, applyAbAttrs } from "#app/data/ability";
+import { BlockNonDirectDamageAbAttr, ChangeMovePriorityAbAttr, InfiltratorAbAttr, ProtectStatAbAttr, applyAbAttrs } from "#app/data/ability";
 import { Stat } from "#enums/stat";
 import { CommonAnim, CommonBattleAnim } from "#app/data/battle-anims";
 import i18next from "i18next";
@@ -130,7 +130,18 @@ export class MistTag extends ArenaTag {
    * to flag the stat reduction as cancelled
    * @returns `true` if a stat reduction was cancelled; `false` otherwise
    */
-  override apply(arena: Arena, simulated: boolean, cancelled: BooleanHolder): boolean {
+  override apply(arena: Arena, simulated: boolean, attacker: Pokemon, cancelled: BooleanHolder): boolean {
+    // `StatStageChangePhase` currently doesn't have a reference to the source of stat drops,
+    // so this code currently has no effect on gameplay.
+    if (attacker) {
+      const bypassed = new BooleanHolder(false);
+      // TODO: Allow this to be simulated
+      applyAbAttrs(InfiltratorAbAttr, attacker, null, false, bypassed);
+      if (bypassed.value) {
+        return false;
+      }
+    }
+
     cancelled.value = true;
 
     if (!simulated) {
@@ -169,12 +180,18 @@ export class WeakenMoveScreenTag extends ArenaTag {
    *
    * @param arena the {@linkcode Arena} where the move is applied.
    * @param simulated n/a
+   * @param attacker the attacking {@linkcode Pokemon}
    * @param moveCategory the attacking move's {@linkcode MoveCategory}.
    * @param damageMultiplier A {@linkcode NumberHolder} containing the damage multiplier
    * @returns `true` if the attacking move was weakened; `false` otherwise.
    */
-  override apply(arena: Arena, simulated: boolean, moveCategory: MoveCategory, damageMultiplier: NumberHolder): boolean {
+  override apply(arena: Arena, simulated: boolean, attacker: Pokemon, moveCategory: MoveCategory, damageMultiplier: NumberHolder): boolean {
     if (this.weakenedCategories.includes(moveCategory)) {
+      const bypassed = new BooleanHolder(false);
+      applyAbAttrs(InfiltratorAbAttr, attacker, null, false, bypassed);
+      if (bypassed.value) {
+        return false;
+      }
       damageMultiplier.value = arena.scene.currentBattle.double ? 2732 / 4096 : 0.5;
       return true;
     }

src/data/battler-tags.ts

@@ -1,29 +1,44 @@
-import { ChargeAnim, CommonAnim, CommonBattleAnim, MoveChargeAnim } from "./battle-anims";
+import BattleScene from "#app/battle-scene";
-import { getPokemonNameWithAffix } from "../messages";
+import {
-import Pokemon, { MoveResult, HitResult } from "../field/pokemon";
+  allAbilities,
-import { StatusEffect } from "./status-effect";
+  applyAbAttrs,
-import * as Utils from "../utils";
+  BlockNonDirectDamageAbAttr,
-import { ChargeAttr, MoveFlags, allMoves, MoveCategory, applyMoveAttrs, StatusCategoryOnAllyAttr, HealOnAllyAttr, ConsecutiveUseDoublePowerAttr } from "./move";
+  FlinchEffectAbAttr,
-import { Type } from "./type";
+  ProtectStatAbAttr,
-import { BlockNonDirectDamageAbAttr, FlinchEffectAbAttr, ReverseDrainAbAttr, applyAbAttrs, ProtectStatAbAttr } from "./ability";
+  ReverseDrainAbAttr
-import { TerrainType } from "./terrain";
+} from "#app/data/ability";
-import { WeatherType } from "./weather";
+import { ChargeAnim, CommonAnim, CommonBattleAnim, MoveChargeAnim } from "#app/data/battle-anims";
-import { allAbilities } from "./ability";
+import Move, {
-import { SpeciesFormChangeManualTrigger } from "./pokemon-forms";
+  allMoves,
-import { Abilities } from "#enums/abilities";
+  applyMoveAttrs,
-import { BattlerTagType } from "#enums/battler-tag-type";
+  ChargeAttr,
-import { Moves } from "#enums/moves";
+  ConsecutiveUseDoublePowerAttr,
-import { Species } from "#enums/species";
+  HealOnAllyAttr,
-import i18next from "#app/plugins/i18n";
+  MoveCategory,
-import { Stat, type BattleStat, type EffectiveStat, EFFECTIVE_STATS, getStatKey } from "#app/enums/stat";
+  MoveFlags,
+  StatusCategoryOnAllyAttr
+} from "#app/data/move";
+import { SpeciesFormChangeManualTrigger } from "#app/data/pokemon-forms";
+import { StatusEffect } from "#app/data/status-effect";
+import { TerrainType } from "#app/data/terrain";
+import { Type } from "#app/data/type";
+import { WeatherType } from "#app/data/weather";
+import Pokemon, { HitResult, MoveResult } from "#app/field/pokemon";
+import { getPokemonNameWithAffix } from "#app/messages";
 import { CommonAnimPhase } from "#app/phases/common-anim-phase";
 import { MoveEffectPhase } from "#app/phases/move-effect-phase";
 import { MovePhase } from "#app/phases/move-phase";
 import { PokemonHealPhase } from "#app/phases/pokemon-heal-phase";
 import { ShowAbilityPhase } from "#app/phases/show-ability-phase";
-import { StatStageChangePhase, StatStageChangeCallback } from "#app/phases/stat-stage-change-phase";
+import { StatStageChangeCallback, StatStageChangePhase } from "#app/phases/stat-stage-change-phase";
-import { PokemonAnimType } from "#app/enums/pokemon-anim-type";
+import i18next from "#app/plugins/i18n";
-import BattleScene from "#app/battle-scene";
+import { BooleanHolder, getFrameMs, NumberHolder, toDmgValue } from "#app/utils";
+import { Abilities } from "#enums/abilities";
+import { BattlerTagType } from "#enums/battler-tag-type";
+import { Moves } from "#enums/moves";
+import { PokemonAnimType } from "#enums/pokemon-anim-type";
+import { Species } from "#enums/species";
+import { EFFECTIVE_STATS, getStatKey, Stat, type BattleStat, type EffectiveStat } from "#enums/stat";
 
 export enum BattlerTagLapseType {
   FAINT,
@@ -33,6 +48,7 @@ export enum BattlerTagLapseType {
   MOVE_EFFECT,
   TURN_END,
   HIT,
+  AFTER_HIT,
   CUSTOM
 }
 
@@ -405,7 +421,7 @@ export class RechargingTag extends BattlerTag {
  */
 export class BeakBlastChargingTag extends BattlerTag {
   constructor() {
-    super(BattlerTagType.BEAK_BLAST_CHARGING, [ BattlerTagLapseType.PRE_MOVE, BattlerTagLapseType.TURN_END ], 1, Moves.BEAK_BLAST);
+    super(BattlerTagType.BEAK_BLAST_CHARGING, [ BattlerTagLapseType.PRE_MOVE, BattlerTagLapseType.TURN_END, BattlerTagLapseType.AFTER_HIT ], 1, Moves.BEAK_BLAST);
   }
 
   onAdd(pokemon: Pokemon): void {
@@ -421,16 +437,13 @@ export class BeakBlastChargingTag extends BattlerTag {
    * to be removed after the source makes a move (or the turn ends, whichever comes first)
    * @param pokemon {@linkcode Pokemon} the owner of this tag
    * @param lapseType {@linkcode BattlerTagLapseType} the type of functionality invoked in battle
-   * @returns `true` if invoked with the CUSTOM lapse type; `false` otherwise
+   * @returns `true` if invoked with the `AFTER_HIT` lapse type
    */
   lapse(pokemon: Pokemon, lapseType: BattlerTagLapseType): boolean {
-    if (lapseType === BattlerTagLapseType.CUSTOM) {
+    if (lapseType === BattlerTagLapseType.AFTER_HIT) {
-      const effectPhase = pokemon.scene.getCurrentPhase();
+      const phaseData = getMoveEffectPhaseData(pokemon);
-      if (effectPhase instanceof MoveEffectPhase) {
+      if (phaseData?.move.hasFlag(MoveFlags.MAKES_CONTACT)) {
-        const attacker = effectPhase.getPokemon();
+        phaseData.attacker.trySetStatus(StatusEffect.BURN, true, pokemon);
-        if (effectPhase.move.getMove().checkFlag(MoveFlags.MAKES_CONTACT, attacker, pokemon)) {
-          attacker.trySetStatus(StatusEffect.BURN, true, pokemon);
-        }
       }
       return true;
     }
@@ -444,11 +457,10 @@ export class BeakBlastChargingTag extends BattlerTag {
  * @see {@link https://bulbapedia.bulbagarden.net/wiki/Shell_Trap_(move) | Shell Trap}
  */
 export class ShellTrapTag extends BattlerTag {
-  public activated: boolean;
+  public activated: boolean = false;
 
   constructor() {
-    super(BattlerTagType.SHELL_TRAP, BattlerTagLapseType.TURN_END, 1);
+    super(BattlerTagType.SHELL_TRAP, [ BattlerTagLapseType.TURN_END, BattlerTagLapseType.AFTER_HIT ], 1);
-    this.activated = false;
   }
 
   onAdd(pokemon: Pokemon): void {
@@ -459,25 +471,33 @@ export class ShellTrapTag extends BattlerTag {
    * "Activates" the shell trap, causing the tag owner to move next.
    * @param pokemon {@linkcode Pokemon} the owner of this tag
    * @param lapseType {@linkcode BattlerTagLapseType} the type of functionality invoked in battle
-   * @returns `true` if invoked with the `CUSTOM` lapse type; `false` otherwise
+   * @returns `true` if invoked with the `AFTER_HIT` lapse type
    */
   lapse(pokemon: Pokemon, lapseType: BattlerTagLapseType): boolean {
-    if (lapseType === BattlerTagLapseType.CUSTOM) {
+    if (lapseType === BattlerTagLapseType.AFTER_HIT) {
-      const shellTrapPhaseIndex = pokemon.scene.phaseQueue.findIndex(
+      const phaseData = getMoveEffectPhaseData(pokemon);
-        phase => phase instanceof MovePhase && phase.pokemon === pokemon
-      );
-      const firstMovePhaseIndex = pokemon.scene.phaseQueue.findIndex(
-        phase => phase instanceof MovePhase
-      );
 
-      if (shellTrapPhaseIndex !== -1 && shellTrapPhaseIndex !== firstMovePhaseIndex) {
+      // Trap should only be triggered by opponent's Physical moves
-        const shellTrapMovePhase = pokemon.scene.phaseQueue.splice(shellTrapPhaseIndex, 1)[0];
+      if (phaseData?.move.category === MoveCategory.PHYSICAL && pokemon.isOpponent(phaseData.attacker)) {
-        pokemon.scene.prependToPhase(shellTrapMovePhase, MovePhase);
+        const shellTrapPhaseIndex = pokemon.scene.phaseQueue.findIndex(
+          phase => phase instanceof MovePhase && phase.pokemon === pokemon
+        );
+        const firstMovePhaseIndex = pokemon.scene.phaseQueue.findIndex(
+          phase => phase instanceof MovePhase
+        );
+
+        // Only shift MovePhase timing if it's not already next up
+        if (shellTrapPhaseIndex !== -1 && shellTrapPhaseIndex !== firstMovePhaseIndex) {
+          const shellTrapMovePhase = pokemon.scene.phaseQueue.splice(shellTrapPhaseIndex, 1)[0];
+          pokemon.scene.prependToPhase(shellTrapMovePhase, MovePhase);
+        }
+
+        this.activated = true;
       }
 
-      this.activated = true;
       return true;
     }
+
     return super.lapse(pokemon, lapseType);
   }
 }
@@ -641,7 +661,7 @@ export class ConfusedTag extends BattlerTag {
       if (pokemon.randSeedInt(3) === 0) {
         const atk = pokemon.getEffectiveStat(Stat.ATK);
         const def = pokemon.getEffectiveStat(Stat.DEF);
-        const damage = Utils.toDmgValue(((((2 * pokemon.level / 5 + 2) * 40 * atk / def) / 50) + 2) * (pokemon.randSeedIntRange(85, 100) / 100));
+        const damage = toDmgValue(((((2 * pokemon.level / 5 + 2) * 40 * atk / def) / 50) + 2) * (pokemon.randSeedIntRange(85, 100) / 100));
         pokemon.scene.queueMessage(i18next.t("battlerTags:confusedLapseHurtItself"));
         pokemon.damageAndUpdate(damage);
         pokemon.battleData.hitCount++;
@@ -812,13 +832,13 @@ export class SeedTag extends BattlerTag {
     if (ret) {
       const source = pokemon.getOpponents().find(o => o.getBattlerIndex() === this.sourceIndex);
       if (source) {
-        const cancelled = new Utils.BooleanHolder(false);
+        const cancelled = new BooleanHolder(false);
         applyAbAttrs(BlockNonDirectDamageAbAttr, pokemon, cancelled);
 
         if (!cancelled.value) {
           pokemon.scene.unshiftPhase(new CommonAnimPhase(pokemon.scene, source.getBattlerIndex(), pokemon.getBattlerIndex(), CommonAnim.LEECH_SEED));
 
-          const damage = pokemon.damageAndUpdate(Utils.toDmgValue(pokemon.getMaxHp() / 8));
+          const damage = pokemon.damageAndUpdate(toDmgValue(pokemon.getMaxHp() / 8));
           const reverseDrain = pokemon.hasAbilityWithAttr(ReverseDrainAbAttr, false);
           pokemon.scene.unshiftPhase(new PokemonHealPhase(pokemon.scene, source.getBattlerIndex(),
             !reverseDrain ? damage : damage * -1,
@@ -838,7 +858,7 @@ export class SeedTag extends BattlerTag {
 
 export class NightmareTag extends BattlerTag {
   constructor() {
-    super(BattlerTagType.NIGHTMARE, BattlerTagLapseType.AFTER_MOVE, 1, Moves.NIGHTMARE);
+    super(BattlerTagType.NIGHTMARE, BattlerTagLapseType.TURN_END, 1, Moves.NIGHTMARE);
   }
 
   onAdd(pokemon: Pokemon): void {
@@ -860,11 +880,11 @@ export class NightmareTag extends BattlerTag {
       pokemon.scene.queueMessage(i18next.t("battlerTags:nightmareLapse", { pokemonNameWithAffix: getPokemonNameWithAffix(pokemon) }));
       pokemon.scene.unshiftPhase(new CommonAnimPhase(pokemon.scene, pokemon.getBattlerIndex(), undefined, CommonAnim.CURSE)); // TODO: Update animation type
 
-      const cancelled = new Utils.BooleanHolder(false);
+      const cancelled = new BooleanHolder(false);
       applyAbAttrs(BlockNonDirectDamageAbAttr, pokemon, cancelled);
 
       if (!cancelled.value) {
-        pokemon.damageAndUpdate(Utils.toDmgValue(pokemon.getMaxHp() / 4));
+        pokemon.damageAndUpdate(toDmgValue(pokemon.getMaxHp() / 4));
       }
     }
 
@@ -1004,7 +1024,7 @@ export class IngrainTag extends TrappedTag {
         new PokemonHealPhase(
           pokemon.scene,
           pokemon.getBattlerIndex(),
-          Utils.toDmgValue(pokemon.getMaxHp() / 16),
+          toDmgValue(pokemon.getMaxHp() / 16),
           i18next.t("battlerTags:ingrainLapse", { pokemonNameWithAffix: getPokemonNameWithAffix(pokemon) }),
           true
         )
@@ -1067,7 +1087,7 @@ export class AquaRingTag extends BattlerTag {
         new PokemonHealPhase(
           pokemon.scene,
           pokemon.getBattlerIndex(),
-          Utils.toDmgValue(pokemon.getMaxHp() / 16),
+          toDmgValue(pokemon.getMaxHp() / 16),
           i18next.t("battlerTags:aquaRingLapse", {
             moveName: this.getMoveName(),
             pokemonName: getPokemonNameWithAffix(pokemon)
@@ -1161,11 +1181,11 @@ export abstract class DamagingTrapTag extends TrappedTag {
       );
       pokemon.scene.unshiftPhase(new CommonAnimPhase(pokemon.scene, pokemon.getBattlerIndex(), undefined, this.commonAnim));
 
-      const cancelled = new Utils.BooleanHolder(false);
+      const cancelled = new BooleanHolder(false);
       applyAbAttrs(BlockNonDirectDamageAbAttr, pokemon, cancelled);
 
       if (!cancelled.value) {
-        pokemon.damageAndUpdate(Utils.toDmgValue(pokemon.getMaxHp() / 8));
+        pokemon.damageAndUpdate(toDmgValue(pokemon.getMaxHp() / 8));
       }
     }
 
@@ -1356,7 +1376,7 @@ export class ContactDamageProtectedTag extends ProtectedTag {
       if (effectPhase instanceof MoveEffectPhase && effectPhase.move.getMove().hasFlag(MoveFlags.MAKES_CONTACT)) {
         const attacker = effectPhase.getPokemon();
         if (!attacker.hasAbilityWithAttr(BlockNonDirectDamageAbAttr)) {
-          attacker.damageAndUpdate(Utils.toDmgValue(attacker.getMaxHp() * (1 / this.damageRatio)), HitResult.OTHER);
+          attacker.damageAndUpdate(toDmgValue(attacker.getMaxHp() * (1 / this.damageRatio)), HitResult.OTHER);
         }
       }
     }
@@ -1709,7 +1729,7 @@ export class SemiInvulnerableTag extends BattlerTag {
   onRemove(pokemon: Pokemon): void {
     // Wait 2 frames before setting visible for battle animations that don't immediately show the sprite invisible
     pokemon.scene.tweens.addCounter({
-      duration: Utils.getFrameMs(2),
+      duration: getFrameMs(2),
       onComplete: () => pokemon.setVisible(true)
     });
   }
@@ -1860,12 +1880,12 @@ export class SaltCuredTag extends BattlerTag {
     if (ret) {
       pokemon.scene.unshiftPhase(new CommonAnimPhase(pokemon.scene, pokemon.getBattlerIndex(), pokemon.getBattlerIndex(), CommonAnim.SALT_CURE));
 
-      const cancelled = new Utils.BooleanHolder(false);
+      const cancelled = new BooleanHolder(false);
       applyAbAttrs(BlockNonDirectDamageAbAttr, pokemon, cancelled);
 
       if (!cancelled.value) {
         const pokemonSteelOrWater = pokemon.isOfType(Type.STEEL) || pokemon.isOfType(Type.WATER);
-        pokemon.damageAndUpdate(Utils.toDmgValue(pokemonSteelOrWater ? pokemon.getMaxHp() / 4 : pokemon.getMaxHp() / 8));
+        pokemon.damageAndUpdate(toDmgValue(pokemonSteelOrWater ? pokemon.getMaxHp() / 4 : pokemon.getMaxHp() / 8));
 
         pokemon.scene.queueMessage(
           i18next.t("battlerTags:saltCuredLapse", {
@@ -1907,11 +1927,11 @@ export class CursedTag extends BattlerTag {
     if (ret) {
       pokemon.scene.unshiftPhase(new CommonAnimPhase(pokemon.scene, pokemon.getBattlerIndex(), pokemon.getBattlerIndex(), CommonAnim.SALT_CURE));
 
-      const cancelled = new Utils.BooleanHolder(false);
+      const cancelled = new BooleanHolder(false);
       applyAbAttrs(BlockNonDirectDamageAbAttr, pokemon, cancelled);
 
       if (!cancelled.value) {
-        pokemon.damageAndUpdate(Utils.toDmgValue(pokemon.getMaxHp() / 4));
+        pokemon.damageAndUpdate(toDmgValue(pokemon.getMaxHp() / 4));
         pokemon.scene.queueMessage(i18next.t("battlerTags:cursedLapse", { pokemonNameWithAffix: getPokemonNameWithAffix(pokemon) }));
       }
     }
@@ -2173,7 +2193,7 @@ export class GulpMissileTag extends BattlerTag {
         return true;
       }
 
-      const cancelled = new Utils.BooleanHolder(false);
+      const cancelled = new BooleanHolder(false);
       applyAbAttrs(BlockNonDirectDamageAbAttr, attacker, cancelled);
 
       if (!cancelled.value) {
@@ -2289,7 +2309,7 @@ export class HealBlockTag extends MoveRestrictionBattlerTag {
    * @returns `true` if the move cannot be used because the target is an ally
    */
   override isMoveTargetRestricted(move: Moves, user: Pokemon, target: Pokemon) {
-    const moveCategory = new Utils.IntegerHolder(allMoves[move].category);
+    const moveCategory = new NumberHolder(allMoves[move].category);
     applyMoveAttrs(StatusCategoryOnAllyAttr, user, target, allMoves[move], moveCategory);
     if (allMoves[move].hasAttr(HealOnAllyAttr) && moveCategory.value === MoveCategory.STATUS ) {
       return true;
@@ -2506,7 +2526,7 @@ export class MysteryEncounterPostSummonTag extends BattlerTag {
     const ret = super.lapse(pokemon, lapseType);
 
     if (lapseType === BattlerTagLapseType.CUSTOM) {
-      const cancelled = new Utils.BooleanHolder(false);
+      const cancelled = new BooleanHolder(false);
       applyAbAttrs(ProtectStatAbAttr, pokemon, cancelled);
       if (!cancelled.value) {
         if (pokemon.mysteryEncounterBattleEffects) {
@@ -2955,3 +2975,22 @@ export function loadBattlerTag(source: BattlerTag | any): BattlerTag {
   tag.loadTag(source);
   return tag;
 }
+
+/**
+ * Helper function to verify that the current phase is a MoveEffectPhase and provide quick access to commonly used fields
+ *
+ * @param pokemon {@linkcode Pokemon} The Pokémon used to access the current phase
+ * @returns null if current phase is not MoveEffectPhase, otherwise Object containing the {@linkcode MoveEffectPhase}, and its
+ * corresponding {@linkcode Move} and user {@linkcode Pokemon}
+ */
+function getMoveEffectPhaseData(pokemon: Pokemon): {phase: MoveEffectPhase, attacker: Pokemon, move: Move} | null {
+  const phase = pokemon.scene.getCurrentPhase();
+  if (phase instanceof MoveEffectPhase) {
+    return {
+      phase     : phase,
+      attacker  : phase.getPokemon(),
+      move      : phase.move.getMove()
+    };
+  }
+  return null;
+}

src/data/move.ts

@@ -8,7 +8,7 @@ import { Constructor, NumberHolder } from "#app/utils";
 import * as Utils from "../utils";
 import { WeatherType } from "./weather";
 import { ArenaTagSide, ArenaTrapTag, WeakenMoveTypeTag } from "./arena-tag";
-import { allAbilities, AllyMoveCategoryPowerBoostAbAttr, applyAbAttrs, applyPostAttackAbAttrs, applyPreAttackAbAttrs, applyPreDefendAbAttrs, BlockItemTheftAbAttr, BlockNonDirectDamageAbAttr, BlockOneHitKOAbAttr, BlockRecoilDamageAttr, ConfusionOnStatusEffectAbAttr, FieldMoveTypePowerBoostAbAttr, FieldPreventExplosiveMovesAbAttr, ForceSwitchOutImmunityAbAttr, HealFromBerryUseAbAttr, IgnoreContactAbAttr, IgnoreMoveEffectsAbAttr, IgnoreProtectOnContactAbAttr, MaxMultiHitAbAttr, MoveAbilityBypassAbAttr, MoveEffectChanceMultiplierAbAttr, MoveTypeChangeAbAttr, ReverseDrainAbAttr, UncopiableAbilityAbAttr, UnsuppressableAbilityAbAttr, UnswappableAbilityAbAttr, UserFieldMoveTypePowerBoostAbAttr, VariableMovePowerAbAttr, WonderSkinAbAttr } from "./ability";
+import { allAbilities, AllyMoveCategoryPowerBoostAbAttr, applyAbAttrs, applyPostAttackAbAttrs, applyPreAttackAbAttrs, applyPreDefendAbAttrs, BlockItemTheftAbAttr, BlockNonDirectDamageAbAttr, BlockOneHitKOAbAttr, BlockRecoilDamageAttr, ConfusionOnStatusEffectAbAttr, FieldMoveTypePowerBoostAbAttr, FieldPreventExplosiveMovesAbAttr, ForceSwitchOutImmunityAbAttr, HealFromBerryUseAbAttr, IgnoreContactAbAttr, IgnoreMoveEffectsAbAttr, IgnoreProtectOnContactAbAttr, InfiltratorAbAttr, MaxMultiHitAbAttr, MoveAbilityBypassAbAttr, MoveEffectChanceMultiplierAbAttr, MoveTypeChangeAbAttr, ReverseDrainAbAttr, UncopiableAbilityAbAttr, UnsuppressableAbilityAbAttr, UnswappableAbilityAbAttr, UserFieldMoveTypePowerBoostAbAttr, VariableMovePowerAbAttr, WonderSkinAbAttr } from "./ability";
 import { AttackTypeBoosterModifier, BerryModifier, PokemonHeldItemModifier, PokemonMoveAccuracyBoosterModifier, PokemonMultiHitModifier, PreserveBerryModifier } from "../modifier/modifier";
 import { BattlerIndex, BattleType } from "../battle";
 import { TerrainType } from "./terrain";
@@ -346,7 +346,11 @@ export default class Move implements Localizable {
       return false;
     }
 
-    return !user.hasAbility(Abilities.INFILTRATOR)
+    const bypassed = new Utils.BooleanHolder(false);
+    // TODO: Allow this to be simulated
+    applyAbAttrs(InfiltratorAbAttr, user, null, false, bypassed);
+
+    return !bypassed.value
         && !this.hasFlag(MoveFlags.SOUND_BASED)
         && !this.hasFlag(MoveFlags.IGNORE_SUBSTITUTE);
   }
@@ -2074,7 +2078,7 @@ export class StatusEffectAttr extends MoveEffectAttr {
         }
       }
 
-      if (user !== target && target.scene.arena.getTagOnSide(ArenaTagType.SAFEGUARD, target.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY)) {
+      if (user !== target && target.isSafeguarded(user)) {
         if (move.category === MoveCategory.STATUS) {
           user.scene.queueMessage(i18next.t("moveTriggers:safeguard", { targetName: getPokemonNameWithAffix(target) }));
         }
@@ -5161,7 +5165,7 @@ export class ConfuseAttr extends AddBattlerTagAttr {
   }
 
   apply(user: Pokemon, target: Pokemon, move: Move, args: any[]): boolean {
-    if (!this.selfTarget && target.scene.arena.getTagOnSide(ArenaTagType.SAFEGUARD, target.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY)) {
+    if (!this.selfTarget && target.isSafeguarded(user)) {
       if (move.category === MoveCategory.STATUS) {
         user.scene.queueMessage(i18next.t("moveTriggers:safeguard", { targetName: getPokemonNameWithAffix(target) }));
       }
@@ -7598,6 +7602,7 @@ export function initMoves() {
       .ignoresVirtual(),
     new StatusMove(Moves.TRANSFORM, Type.NORMAL, -1, 10, -1, 0, 1)
       .attr(TransformAttr)
+      .condition((user, target, move) => !target.getTag(BattlerTagType.SUBSTITUTE))
       .ignoresProtect(),
     new AttackMove(Moves.BUBBLE, Type.WATER, MoveCategory.SPECIAL, 40, 100, 30, 10, 0, 1)
       .attr(StatStageChangeAttr, [ Stat.SPD ], -1)
@@ -8028,7 +8033,7 @@ export function initMoves() {
       .attr(RemoveScreensAttr),
     new StatusMove(Moves.YAWN, Type.NORMAL, -1, 10, -1, 0, 3)
       .attr(AddBattlerTagAttr, BattlerTagType.DROWSY, false, true)
-      .condition((user, target, move) => !target.status && !target.scene.arena.getTagOnSide(ArenaTagType.SAFEGUARD, target.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY)),
+      .condition((user, target, move) => !target.status && !target.isSafeguarded(user)),
     new AttackMove(Moves.KNOCK_OFF, Type.DARK, MoveCategory.PHYSICAL, 65, 100, 20, -1, 0, 3)
       .attr(MovePowerMultiplierAttr, (user, target, move) => target.getHeldItems().filter(i => i.isTransferable).length > 0 ? 1.5 : 1)
       .attr(RemoveHeldItemAttr, false),

src/field/pokemon.ts

@@ -22,7 +22,7 @@ import { reverseCompatibleTms, tmSpecies, tmPoolTiers } from "#app/data/balance/
 import { BattlerTag, BattlerTagLapseType, EncoreTag, GroundedTag, HighestStatBoostTag, SubstituteTag, TypeImmuneTag, getBattlerTag, SemiInvulnerableTag, TypeBoostTag, MoveRestrictionBattlerTag, ExposedTag, DragonCheerTag, CritBoostTag, TrappedTag, TarShotTag, AutotomizedTag, PowerTrickTag } from "../data/battler-tags";
 import { WeatherType } from "#app/data/weather";
 import { ArenaTagSide, NoCritTag, WeakenMoveScreenTag } from "#app/data/arena-tag";
-import { Ability, AbAttr, StatMultiplierAbAttr, BlockCritAbAttr, BonusCritAbAttr, BypassBurnDamageReductionAbAttr, FieldPriorityMoveImmunityAbAttr, IgnoreOpponentStatStagesAbAttr, MoveImmunityAbAttr, PreDefendFullHpEndureAbAttr, ReceivedMoveDamageMultiplierAbAttr, ReduceStatusEffectDurationAbAttr, StabBoostAbAttr, StatusEffectImmunityAbAttr, TypeImmunityAbAttr, WeightMultiplierAbAttr, allAbilities, applyAbAttrs, applyStatMultiplierAbAttrs, applyPreApplyBattlerTagAbAttrs, applyPreAttackAbAttrs, applyPreDefendAbAttrs, applyPreSetStatusAbAttrs, UnsuppressableAbilityAbAttr, SuppressFieldAbilitiesAbAttr, NoFusionAbilityAbAttr, MultCritAbAttr, IgnoreTypeImmunityAbAttr, DamageBoostAbAttr, IgnoreTypeStatusEffectImmunityAbAttr, ConditionalCritAbAttr, applyFieldStatMultiplierAbAttrs, FieldMultiplyStatAbAttr, AddSecondStrikeAbAttr, UserFieldStatusEffectImmunityAbAttr, UserFieldBattlerTagImmunityAbAttr, BattlerTagImmunityAbAttr, MoveTypeChangeAbAttr, FullHpResistTypeAbAttr, applyCheckTrappedAbAttrs, CheckTrappedAbAttr, PostSetStatusAbAttr, applyPostSetStatusAbAttrs } from "#app/data/ability";
+import { Ability, AbAttr, StatMultiplierAbAttr, BlockCritAbAttr, BonusCritAbAttr, BypassBurnDamageReductionAbAttr, FieldPriorityMoveImmunityAbAttr, IgnoreOpponentStatStagesAbAttr, MoveImmunityAbAttr, PreDefendFullHpEndureAbAttr, ReceivedMoveDamageMultiplierAbAttr, ReduceStatusEffectDurationAbAttr, StabBoostAbAttr, StatusEffectImmunityAbAttr, TypeImmunityAbAttr, WeightMultiplierAbAttr, allAbilities, applyAbAttrs, applyStatMultiplierAbAttrs, applyPreApplyBattlerTagAbAttrs, applyPreAttackAbAttrs, applyPreDefendAbAttrs, applyPreSetStatusAbAttrs, UnsuppressableAbilityAbAttr, SuppressFieldAbilitiesAbAttr, NoFusionAbilityAbAttr, MultCritAbAttr, IgnoreTypeImmunityAbAttr, DamageBoostAbAttr, IgnoreTypeStatusEffectImmunityAbAttr, ConditionalCritAbAttr, applyFieldStatMultiplierAbAttrs, FieldMultiplyStatAbAttr, AddSecondStrikeAbAttr, UserFieldStatusEffectImmunityAbAttr, UserFieldBattlerTagImmunityAbAttr, BattlerTagImmunityAbAttr, MoveTypeChangeAbAttr, FullHpResistTypeAbAttr, applyCheckTrappedAbAttrs, CheckTrappedAbAttr, PostSetStatusAbAttr, applyPostSetStatusAbAttrs, InfiltratorAbAttr } from "#app/data/ability";
 import PokemonData from "#app/system/pokemon-data";
 import { BattlerIndex } from "#app/battle";
 import { Mode } from "#app/ui/ui";
@@ -2289,6 +2289,15 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
     this.levelExp = this.exp - getLevelTotalExp(this.level, this.species.growthRate);
   }
 
+  /**
+   * Compares if `this` and {@linkcode target} are on the same team.
+   * @param target the {@linkcode Pokemon} to compare against.
+   * @returns `true` if the two pokemon are allies, `false` otherwise
+   */
+  public isOpponent(target: Pokemon): boolean {
+    return this.isPlayer() !== target.isPlayer();
+  }
+
   getOpponent(targetIndex: integer): Pokemon | null {
     const ret = this.getOpponents()[targetIndex];
     if (ret.summonData) {
@@ -2609,7 +2618,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
 
     /** Reduces damage if this Pokemon has a relevant screen (e.g. Light Screen for special attacks) */
     const screenMultiplier = new Utils.NumberHolder(1);
-    this.scene.arena.applyTagsForSide(WeakenMoveScreenTag, defendingSide, simulated, moveCategory, screenMultiplier);
+    this.scene.arena.applyTagsForSide(WeakenMoveScreenTag, defendingSide, simulated, source, moveCategory, screenMultiplier);
 
     /**
      * For each {@linkcode HitsTagAttr} the move has, doubles the damage of the move if:
@@ -3351,13 +3360,12 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
       }
     }
 
-    const types = this.getTypes(true, true);
+    if (sourcePokemon && sourcePokemon !== this && this.isSafeguarded(sourcePokemon)) {
-
-    const defendingSide = this.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY;
-    if (sourcePokemon && sourcePokemon !== this && this.scene.arena.getTagOnSide(ArenaTagType.SAFEGUARD, defendingSide)) {
       return false;
     }
 
+    const types = this.getTypes(true, true);
+
     switch (effect) {
       case StatusEffect.POISON:
       case StatusEffect.TOXIC:
@@ -3503,6 +3511,23 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
     }
   }
 
+  /**
+   * Checks if this Pokemon is protected by Safeguard
+   * @param attacker the {@linkcode Pokemon} inflicting status on this Pokemon
+   * @returns `true` if this Pokemon is protected by Safeguard; `false` otherwise.
+   */
+  isSafeguarded(attacker: Pokemon): boolean {
+    const defendingSide = this.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY;
+    if (this.scene.arena.getTagOnSide(ArenaTagType.SAFEGUARD, defendingSide)) {
+      const bypassed = new Utils.BooleanHolder(false);
+      if (attacker) {
+        applyAbAttrs(InfiltratorAbAttr, attacker, null, false, bypassed);
+      }
+      return !bypassed.value;
+    }
+    return false;
+  }
+
   primeSummonData(summonDataPrimer: PokemonSummonData): void {
     this.summonDataPrimer = summonDataPrimer;
   }

src/phases/move-effect-phase.ts

@@ -280,10 +280,8 @@ export class MoveEffectPhase extends PokemonPhase {
                           if (!user.isPlayer() && this.move.getMove() instanceof AttackMove) {
                             user.scene.applyShuffledModifiers(this.scene, EnemyAttackStatusEffectChanceModifier, false, target);
                           }
-                          target.lapseTag(BattlerTagType.BEAK_BLAST_CHARGING);
+                          target.lapseTags(BattlerTagLapseType.AFTER_HIT);
-                          if (move.category === MoveCategory.PHYSICAL && user.isPlayer() !== target.isPlayer()) {
+
-                            target.lapseTag(BattlerTagType.SHELL_TRAP);
-                          }
                         })).then(() => {
                           // Apply the user's post-attack ability effects
                           applyPostAttackAbAttrs(PostAttackAbAttr, user, target, this.move.getMove(), hitResult).then(() => {

src/phases/stat-stage-change-phase.ts

@@ -64,7 +64,8 @@ export class StatStageChangePhase extends PokemonPhase {
       const cancelled = new BooleanHolder(false);
 
       if (!this.selfTarget && stages.value < 0) {
-        this.scene.arena.applyTagsForSide(MistTag, pokemon.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY, false, cancelled);
+        // TODO: add a reference to the source of the stat change to fix Infiltrator interaction
+        this.scene.arena.applyTagsForSide(MistTag, pokemon.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY, false, null, false, cancelled);
       }
 
       if (!cancelled.value && !this.selfTarget && stages.value < 0) {

src/test/abilities/infiltrator.test.ts

@@ -0,0 +1,107 @@
+import { ArenaTagSide } from "#app/data/arena-tag";
+import { allMoves } from "#app/data/move";
+import { ArenaTagType } from "#enums/arena-tag-type";
+import { BattlerTagType } from "#enums/battler-tag-type";
+import { Stat } from "#enums/stat";
+import { StatusEffect } from "#enums/status-effect";
+import { Abilities } from "#enums/abilities";
+import { Moves } from "#enums/moves";
+import { Species } from "#enums/species";
+import GameManager from "#test/utils/gameManager";
+import Phaser from "phaser";
+import { afterEach, beforeAll, beforeEach, describe, expect, it } from "vitest";
+
+describe("Abilities - Infiltrator", () => {
+  let phaserGame: Phaser.Game;
+  let game: GameManager;
+
+  beforeAll(() => {
+    phaserGame = new Phaser.Game({
+      type: Phaser.HEADLESS,
+    });
+  });
+
+  afterEach(() => {
+    game.phaseInterceptor.restoreOg();
+  });
+
+  beforeEach(() => {
+    game = new GameManager(phaserGame);
+    game.override
+      .moveset([ Moves.TACKLE, Moves.WATER_GUN, Moves.SPORE, Moves.BABY_DOLL_EYES ])
+      .ability(Abilities.INFILTRATOR)
+      .battleType("single")
+      .disableCrits()
+      .enemySpecies(Species.SNORLAX)
+      .enemyAbility(Abilities.BALL_FETCH)
+      .enemyMoveset(Moves.SPLASH)
+      .startingLevel(100)
+      .enemyLevel(100);
+  });
+
+  it.each([
+    { effectName: "Light Screen", tagType: ArenaTagType.LIGHT_SCREEN, move: Moves.WATER_GUN },
+    { effectName: "Reflect", tagType: ArenaTagType.REFLECT, move: Moves.TACKLE },
+    { effectName: "Aurora Veil", tagType: ArenaTagType.AURORA_VEIL, move: Moves.TACKLE }
+  ])("should bypass the target's $effectName", async ({ tagType, move }) => {
+    await game.classicMode.startBattle([ Species.MAGIKARP ]);
+
+    const player = game.scene.getPlayerPokemon()!;
+    const enemy = game.scene.getEnemyPokemon()!;
+
+    const preScreenDmg = enemy.getAttackDamage(player, allMoves[move]).damage;
+
+    game.scene.arena.addTag(tagType, 1, Moves.NONE, enemy.id, ArenaTagSide.ENEMY, true);
+
+    const postScreenDmg = enemy.getAttackDamage(player, allMoves[move]).damage;
+
+    expect(postScreenDmg).toBe(preScreenDmg);
+    expect(player.battleData.abilitiesApplied[0]).toBe(Abilities.INFILTRATOR);
+  });
+
+  it("should bypass the target's Safeguard", async () => {
+    await game.classicMode.startBattle([ Species.MAGIKARP ]);
+
+    const player = game.scene.getPlayerPokemon()!;
+    const enemy = game.scene.getEnemyPokemon()!;
+
+    game.scene.arena.addTag(ArenaTagType.SAFEGUARD, 1, Moves.NONE, enemy.id, ArenaTagSide.ENEMY, true);
+
+    game.move.select(Moves.SPORE);
+
+    await game.phaseInterceptor.to("BerryPhase", false);
+    expect(enemy.status?.effect).toBe(StatusEffect.SLEEP);
+    expect(player.battleData.abilitiesApplied[0]).toBe(Abilities.INFILTRATOR);
+  });
+
+  // TODO: fix this interaction to pass this test
+  it.skip("should bypass the target's Mist", async () => {
+    await game.classicMode.startBattle([ Species.MAGIKARP ]);
+
+    const player = game.scene.getPlayerPokemon()!;
+    const enemy = game.scene.getEnemyPokemon()!;
+
+    game.scene.arena.addTag(ArenaTagType.MIST, 1, Moves.NONE, enemy.id, ArenaTagSide.ENEMY, true);
+
+    game.move.select(Moves.BABY_DOLL_EYES);
+
+    await game.phaseInterceptor.to("MoveEndPhase");
+    expect(enemy.getStatStage(Stat.ATK)).toBe(-1);
+    expect(player.battleData.abilitiesApplied[0]).toBe(Abilities.INFILTRATOR);
+  });
+
+  it("should bypass the target's Substitute", async () => {
+    await game.classicMode.startBattle([ Species.MAGIKARP ]);
+
+    const player = game.scene.getPlayerPokemon()!;
+    const enemy = game.scene.getEnemyPokemon()!;
+
+    enemy.addTag(BattlerTagType.SUBSTITUTE, 1, Moves.NONE, enemy.id);
+
+    game.move.select(Moves.BABY_DOLL_EYES);
+
+    await game.phaseInterceptor.to("MoveEndPhase");
+    expect(enemy.getStatStage(Stat.ATK)).toBe(-1);
+    expect(player.battleData.abilitiesApplied[0]).toBe(Abilities.INFILTRATOR);
+  });
+});

src/test/moves/aurora_veil.test.ts

@@ -111,7 +111,7 @@ const getMockedMoveDamage = (defender: Pokemon, attacker: Pokemon, move: Move) =
   const side = defender.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY;
 
   if (defender.scene.arena.getTagOnSide(ArenaTagType.AURORA_VEIL, side)) {
-    defender.scene.arena.applyTagsForSide(ArenaTagType.AURORA_VEIL, side, false, move.category, multiplierHolder);
+    defender.scene.arena.applyTagsForSide(ArenaTagType.AURORA_VEIL, side, false, attacker, move.category, multiplierHolder);
   }
 
   return move.power * multiplierHolder.value;

src/test/moves/light_screen.test.ts

@@ -94,7 +94,7 @@ const getMockedMoveDamage = (defender: Pokemon, attacker: Pokemon, move: Move) =
   const side = defender.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY;
 
   if (defender.scene.arena.getTagOnSide(ArenaTagType.LIGHT_SCREEN, side)) {
-    defender.scene.arena.applyTagsForSide(ArenaTagType.LIGHT_SCREEN, side, false, move.category, multiplierHolder);
+    defender.scene.arena.applyTagsForSide(ArenaTagType.LIGHT_SCREEN, side, false, attacker, move.category, multiplierHolder);
   }
 
   return move.power * multiplierHolder.value;

src/test/moves/nightmare.test.ts

@@ -0,0 +1,54 @@
+import { CommandPhase } from "#app/phases/command-phase";
+import { TurnInitPhase } from "#app/phases/turn-init-phase";
+import { Abilities } from "#enums/abilities";
+import { Moves } from "#enums/moves";
+import { Species } from "#enums/species";
+import GameManager from "#test/utils/gameManager";
+import Phaser from "phaser";
+import { afterEach, beforeAll, beforeEach, describe, expect, it } from "vitest";
+import { StatusEffect } from "#app/data/status-effect";
+
+describe("Moves - Nightmare", () => {
+  let phaserGame: Phaser.Game;
+  let game: GameManager;
+
+  beforeAll(() => {
+    phaserGame = new Phaser.Game({
+      type: Phaser.HEADLESS,
+    });
+  });
+
+  afterEach(() => {
+    game.phaseInterceptor.restoreOg();
+  });
+
+  beforeEach(() => {
+    game = new GameManager(phaserGame);
+
+    game.override.battleType("single")
+      .enemySpecies(Species.RATTATA)
+      .enemyMoveset(Moves.SPLASH)
+      .enemyAbility(Abilities.BALL_FETCH)
+      .enemyStatusEffect(StatusEffect.SLEEP)
+      .startingLevel(5)
+      .moveset([ Moves.NIGHTMARE, Moves.SPLASH ]);
+  });
+
+  it("lowers enemy hp by 1/4 each turn while asleep", async () => {
+    await game.classicMode.startBattle([ Species.HYPNO ]);
+
+    const enemyPokemon = game.scene.getEnemyPokemon()!;
+    const enemyMaxHP = enemyPokemon.hp;
+    game.move.select(Moves.NIGHTMARE);
+    await game.phaseInterceptor.to(TurnInitPhase);
+
+    expect(enemyPokemon.hp).toBe(enemyMaxHP - Math.floor(enemyMaxHP / 4));
+
+    // take a second turn to make sure damage occurs again
+    await game.phaseInterceptor.to(CommandPhase);
+    game.move.select(Moves.SPLASH);
+
+    await game.phaseInterceptor.to(TurnInitPhase);
+    expect(enemyPokemon.hp).toBe(enemyMaxHP - Math.floor(enemyMaxHP / 4) - Math.floor(enemyMaxHP / 4));
+  });
+});

src/test/moves/reflect.test.ts

@@ -94,7 +94,7 @@ const getMockedMoveDamage = (defender: Pokemon, attacker: Pokemon, move: Move) =
   const side = defender.isPlayer() ? ArenaTagSide.PLAYER : ArenaTagSide.ENEMY;
 
   if (defender.scene.arena.getTagOnSide(ArenaTagType.REFLECT, side)) {
-    defender.scene.arena.applyTagsForSide(ArenaTagType.REFLECT, side, false, move.category, multiplierHolder);
+    defender.scene.arena.applyTagsForSide(ArenaTagType.REFLECT, side, false, attacker, move.category, multiplierHolder);
   }
 
   return move.power * multiplierHolder.value;