Make tera retain until forced recall or faint, regain on biome change

src/battle-scene.ts

@@ -1372,6 +1372,7 @@ export default class BattleScene extends SceneBase {
 
         for (const pokemon of this.getPlayerParty()) {
           pokemon.resetBattleData();
+          pokemon.resetTera();
           applyPostBattleInitAbAttrs(PostBattleInitAbAttr, pokemon);
         }
 

src/field/arena.ts

@@ -44,6 +44,7 @@ export class Arena {
   public bgm: string;
   public ignoreAbilities: boolean;
   public ignoringEffectSource: BattlerIndex | null;
+  public playerTerasUsed: number;
 
   private lastTimeOfDay: TimeOfDay;
 
@@ -58,6 +59,7 @@ export class Arena {
     this.bgm = bgm;
     this.trainerPool = biomeTrainerPools[biome];
     this.updatePoolsForTimeOfDay();
+    this.playerTerasUsed = 0;
   }
 
   init() {

src/field/pokemon.ts

@@ -3796,12 +3796,6 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
 
   resetBattleData(): void {
     this.battleData = new PokemonBattleData();
-    const wasTerastallized = this.isTerastallized;
-    this.isTerastallized = false;
-    if (wasTerastallized) {
-      this.updateSpritePipelineData();
-      globalScene.triggerPokemonFormChange(this, SpeciesFormChangeLapseTeraTrigger);
-    }
   }
 
   resetBattleSummonData(): void {
@@ -3814,6 +3808,15 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
     }
   }
 
+  resetTera(): void {
+    const wasTerastallized = this.isTerastallized;
+    this.isTerastallized = false;
+    if (wasTerastallized) {
+      this.updateSpritePipelineData();
+      globalScene.triggerPokemonFormChange(this, SpeciesFormChangeLapseTeraTrigger);
+    }
+  }
+
   resetTurnData(): void {
     this.turnData = new PokemonTurnData();
   }

src/phases/faint-phase.ts

@@ -109,6 +109,8 @@ export class FaintPhase extends PokemonPhase {
     globalScene.queueMessage(i18next.t("battle:fainted", { pokemonNameWithAffix: getPokemonNameWithAffix(pokemon) }), null, true);
     globalScene.triggerPokemonFormChange(pokemon, SpeciesFormChangeActiveTrigger, true);
 
+    pokemon.resetTera();
+
     if (pokemon.turnData?.attacksReceived?.length) {
       const lastAttack = pokemon.turnData.attacksReceived[0];
       applyPostFaintAbAttrs(PostFaintAbAttr, pokemon, globalScene.getPokemonById(lastAttack.sourceId)!, new PokemonMove(lastAttack.move).getMove(), lastAttack.result); // TODO: is this bang correct?

src/phases/party-heal-phase.ts

@@ -36,5 +36,6 @@ export class PartyHealPhase extends BattlePhase {
         globalScene.ui.fadeIn(500).then(() => this.end());
       });
     });
+    globalScene.arena.playerTerasUsed = 0;
   }
 }

src/phases/tera-phase.ts

@@ -6,7 +6,8 @@ import { globalScene } from "#app/global-scene";
 import { Type } from "#app/enums/type";
 import { achvs } from "#app/system/achv";
 import { SpeciesFormChangeTeraTrigger } from "#app/data/pokemon-forms";
-import { CommonAnim, CommonBattleAnim } from "#app/data/battle-anims";
+import { CommonAnim } from "#app/data/battle-anims";
+import { CommonAnimPhase } from "./common-anim-phase";
 
 export class TeraPhase extends BattlePhase {
   public pokemon: Pokemon;
@@ -32,9 +33,8 @@ export class TeraPhase extends BattlePhase {
     // parent.add(teraburst);
     // this.pokemon.scene.time.delayedCall(Utils.fixedInt(Math.floor((1000 / 12) * 13)), () => teraburst.destroy());
 
-    new CommonBattleAnim(CommonAnim.TERASTALLIZE, this.pokemon).play();
     globalScene.queueMessage(getPokemonNameWithAffix(this.pokemon) + " terrastallized into a " + i18next.t(`pokemonInfo:Type.${Type[this.pokemon.teraType]}`) + " type!"); // TODO: Localize this
-    // this.scene.unshiftPhase(new CommonAnimPhase(this.scene, this.pokemon.getBattlerIndex(), undefined, CommonAnim.???));
+    globalScene.unshiftPhase(new CommonAnimPhase(this.pokemon.getBattlerIndex(), this.pokemon.getBattlerIndex(), CommonAnim.TERASTALLIZE, false));
 
     this.end();
   }
@@ -44,6 +44,10 @@ export class TeraPhase extends BattlePhase {
     this.pokemon.isTerastallized = true;
     this.pokemon.updateSpritePipelineData();
 
+    if (this.pokemon.isPlayer()) {
+      globalScene.arena.playerTerasUsed += 1;
+    }
+
     globalScene.triggerPokemonFormChange(this.pokemon, SpeciesFormChangeTeraTrigger);
 
     if (this.pokemon.isPlayer()) {

src/system/arena-data.ts

@@ -10,12 +10,14 @@ export default class ArenaData {
   public weather: Weather | null;
   public terrain: Terrain | null;
   public tags: ArenaTag[];
+  public playerTerasUsed: number;
 
   constructor(source: Arena | any) {
     const sourceArena = source instanceof Arena ? source as Arena : null;
     this.biome = sourceArena ? sourceArena.biomeType : source.biome;
     this.weather = sourceArena ? sourceArena.weather : source.weather ? new Weather(source.weather.weatherType, source.weather.turnsLeft) : null;
     this.terrain = sourceArena ? sourceArena.terrain : source.terrain ? new Terrain(source.terrain.terrainType, source.terrain.turnsLeft) : null;
+    this.playerTerasUsed = sourceArena ? sourceArena.playerTerasUsed : source.playerTerasUsed;
     this.tags = [];
 
     if (source.tags) {

src/system/game-data.ts

@@ -1082,6 +1082,8 @@ export class GameData {
           globalScene.arena.terrain = sessionData.arena.terrain;
           globalScene.arena.eventTarget.dispatchEvent(new TerrainChangedEvent(TerrainType.NONE, globalScene.arena.terrain?.terrainType!, globalScene.arena.terrain?.turnsLeft!)); // TODO: is this bang correct?
 
+          globalScene.arena.playerTerasUsed = sessionData.arena.playerTerasUsed;
+
           globalScene.arena.tags = sessionData.arena.tags;
           if (globalScene.arena.tags) {
             for (const tag of globalScene.arena.tags) {

src/ui/command-ui-handler.ts

@@ -175,9 +175,9 @@ export default class CommandUiHandler extends UiHandler {
 
   canTera(): boolean {
     const hasTeraMod = !!globalScene.getModifiers(TerastallizeAccessModifier).length;
-    const currentTeras = globalScene.getPlayerParty().filter(p => p.isTerastallized).length;
-    const plannedTera = globalScene.currentBattle.preTurnCommands[0]?.command === Command.TERA;
-    return hasTeraMod && currentTeras < 1 && !plannedTera;
+    const currentTeras = globalScene.arena.playerTerasUsed;
+    const plannedTera = globalScene.currentBattle.preTurnCommands[0]?.command === Command.TERA ? 1 : 0;
+    return hasTeraMod && (currentTeras + plannedTera) < 1;
   }
 
   getCursor(): integer {