[Ability] Heatproof now reduces burn damage by half

src/data/ability.ts

@@ -3428,6 +3428,30 @@ export class BypassBurnDamageReductionAbAttr extends AbAttr {
   }
 }
 
+/**
+ * Causes Pokemon to take reduced damage from the {@linkcode StatusEffect.BURN | Burn} status
+ * @param multiplier Multiplied with the damage taken
+*/
+export class ReduceBurnDamageAbAttr extends AbAttr {
+  constructor(protected multiplier: number) {
+    super(false);
+  }
+
+  /**
+   * Applies the damage reduction
+   * @param pokemon N/A
+   * @param passive N/A
+   * @param cancelled N/A
+   * @param args `[0]` {@linkcode Utils.NumberHolder} The damage value being modified
+   * @returns `true`
+   */
+  apply(pokemon: Pokemon, passive: boolean, cancelled: Utils.BooleanHolder, args: any[]): boolean {
+    (args[0] as Utils.NumberHolder).value = Math.max(Math.floor((args[0] as Utils.NumberHolder).value * this.multiplier), 1);
+
+    return true;
+  }
+}
+
 export class DoubleBerryEffectAbAttr extends AbAttr {
   apply(pokemon: Pokemon, passive: boolean, cancelled: Utils.BooleanHolder, args: any[]): boolean {
     (args[0] as Utils.NumberHolder).value *= 2;
@@ -4613,6 +4637,7 @@ export function initAbilities() {
       .unimplemented(),
     new Ability(Abilities.HEATPROOF, 4)
       .attr(ReceivedTypeDamageMultiplierAbAttr, Type.FIRE, 0.5)
+      .attr(ReduceBurnDamageAbAttr, 0.5)
       .ignorable(),
     new Ability(Abilities.SIMPLE, 4)
       .attr(StatChangeMultiplierAbAttr, 2)

src/phases.ts

@@ -25,7 +25,7 @@ import { Starter } from "./ui/starter-select-ui-handler";
 import { Gender } from "./data/gender";
 import { Weather, WeatherType, getRandomWeatherType, getTerrainBlockMessage, getWeatherDamageMessage, getWeatherLapseMessage } from "./data/weather";
 import { ArenaTagSide, ArenaTrapTag, ConditionalProtectTag, MistTag, TrickRoomTag } from "./data/arena-tag";
-import { CheckTrappedAbAttr, PostAttackAbAttr, PostBattleAbAttr, PostDefendAbAttr, PostSummonAbAttr, PostTurnAbAttr, PostWeatherLapseAbAttr, PreSwitchOutAbAttr, PreWeatherDamageAbAttr, ProtectStatAbAttr, RedirectMoveAbAttr, BlockRedirectAbAttr, RunSuccessAbAttr, StatChangeMultiplierAbAttr, SuppressWeatherEffectAbAttr, SyncEncounterNatureAbAttr, applyAbAttrs, applyCheckTrappedAbAttrs, applyPostAttackAbAttrs, applyPostBattleAbAttrs, applyPostDefendAbAttrs, applyPostSummonAbAttrs, applyPostTurnAbAttrs, applyPostWeatherLapseAbAttrs, applyPreStatChangeAbAttrs, applyPreSwitchOutAbAttrs, applyPreWeatherEffectAbAttrs, ChangeMovePriorityAbAttr, applyPostVictoryAbAttrs, PostVictoryAbAttr, BlockNonDirectDamageAbAttr as BlockNonDirectDamageAbAttr, applyPostKnockOutAbAttrs, PostKnockOutAbAttr, PostBiomeChangeAbAttr, PreventBypassSpeedChanceAbAttr, applyPostFaintAbAttrs, PostFaintAbAttr, IncreasePpAbAttr, PostStatChangeAbAttr, applyPostStatChangeAbAttrs, AlwaysHitAbAttr, PreventBerryUseAbAttr, StatChangeCopyAbAttr, PokemonTypeChangeAbAttr, applyPreAttackAbAttrs, applyPostMoveUsedAbAttrs, PostMoveUsedAbAttr, MaxMultiHitAbAttr, HealFromBerryUseAbAttr, IgnoreMoveEffectsAbAttr, BlockStatusDamageAbAttr, BypassSpeedChanceAbAttr, AddSecondStrikeAbAttr } from "./data/ability";
+import { CheckTrappedAbAttr, PostAttackAbAttr, PostBattleAbAttr, PostDefendAbAttr, PostSummonAbAttr, PostTurnAbAttr, PostWeatherLapseAbAttr, PreSwitchOutAbAttr, PreWeatherDamageAbAttr, ProtectStatAbAttr, RedirectMoveAbAttr, BlockRedirectAbAttr, RunSuccessAbAttr, StatChangeMultiplierAbAttr, SuppressWeatherEffectAbAttr, SyncEncounterNatureAbAttr, applyAbAttrs, applyCheckTrappedAbAttrs, applyPostAttackAbAttrs, applyPostBattleAbAttrs, applyPostDefendAbAttrs, applyPostSummonAbAttrs, applyPostTurnAbAttrs, applyPostWeatherLapseAbAttrs, applyPreStatChangeAbAttrs, applyPreSwitchOutAbAttrs, applyPreWeatherEffectAbAttrs, ChangeMovePriorityAbAttr, applyPostVictoryAbAttrs, PostVictoryAbAttr, BlockNonDirectDamageAbAttr as BlockNonDirectDamageAbAttr, applyPostKnockOutAbAttrs, PostKnockOutAbAttr, PostBiomeChangeAbAttr, PreventBypassSpeedChanceAbAttr, applyPostFaintAbAttrs, PostFaintAbAttr, IncreasePpAbAttr, PostStatChangeAbAttr, applyPostStatChangeAbAttrs, AlwaysHitAbAttr, PreventBerryUseAbAttr, StatChangeCopyAbAttr, PokemonTypeChangeAbAttr, applyPreAttackAbAttrs, applyPostMoveUsedAbAttrs, PostMoveUsedAbAttr, MaxMultiHitAbAttr, HealFromBerryUseAbAttr, IgnoreMoveEffectsAbAttr, BlockStatusDamageAbAttr, BypassSpeedChanceAbAttr, AddSecondStrikeAbAttr, ReduceBurnDamageAbAttr } from "./data/ability";
 import { Unlockables, getUnlockableName } from "./system/unlockables";
 import { getBiomeKey } from "./field/arena";
 import { BattleType, BattlerIndex, TurnCommand } from "./battle";
@@ -3815,21 +3815,22 @@ export class PostTurnStatusEffectPhase extends PokemonPhase {
 
       if (!cancelled.value) {
         this.scene.queueMessage(getStatusEffectActivationText(pokemon.status.effect, getPokemonNameWithAffix(pokemon)));
-        let damage: integer = 0;
+        const damage = new Utils.NumberHolder(0);
         switch (pokemon.status.effect) {
         case StatusEffect.POISON:
-          damage = Math.max(pokemon.getMaxHp() >> 3, 1);
+          damage.value = Math.max(pokemon.getMaxHp() >> 3, 1);
           break;
         case StatusEffect.TOXIC:
-          damage = Math.max(Math.floor((pokemon.getMaxHp() / 16) * pokemon.status.turnCount), 1);
+          damage.value = Math.max(Math.floor((pokemon.getMaxHp() / 16) * pokemon.status.turnCount), 1);
           break;
         case StatusEffect.BURN:
-          damage = Math.max(pokemon.getMaxHp() >> 4, 1);
+          damage.value = Math.max(pokemon.getMaxHp() >> 4, 1);
+          applyAbAttrs(ReduceBurnDamageAbAttr, pokemon, null, damage);
           break;
         }
-        if (damage) {
+        if (damage.value) {
           // Set preventEndure flag to avoid pokemon surviving thanks to focus band, sturdy, endure ...
-          this.scene.damageNumberHandler.add(this.getPokemon(), pokemon.damage(damage, false, true));
+          this.scene.damageNumberHandler.add(this.getPokemon(), pokemon.damage(damage.value, false, true));
           pokemon.updateInfo();
         }
         new CommonBattleAnim(CommonAnim.POISON + (pokemon.status.effect - 1), pokemon).play(this.scene, () => this.end());

src/test/abilities/heatproof.test.ts

@@ -0,0 +1,77 @@
+import { Species } from "#app/enums/species.js";
+import { TurnEndPhase } from "#app/phases";
+import GameManager from "#test/utils/gameManager";
+import { getMovePosition } from "#test/utils/gameManagerUtils";
+import { Abilities } from "#enums/abilities";
+import { Moves } from "#enums/moves";
+import Phaser from "phaser";
+import { afterEach, beforeAll, beforeEach, describe, expect, it } from "vitest";
+import { SPLASH_ONLY } from "#test/utils/testUtils";
+import { StatusEffect } from "#app/enums/status-effect.js";
+
+describe("Abilities - Heatproof", () => {
+  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")
+      .disableCrits()
+      .enemySpecies(Species.CHARMANDER)
+      .enemyAbility(Abilities.HEATPROOF)
+      .enemyMoveset(SPLASH_ONLY)
+      .enemyLevel(100)
+      .starterSpecies(Species.CHANDELURE)
+      .ability(Abilities.BALL_FETCH)
+      .moveset([Moves.FLAMETHROWER, Moves.SPLASH])
+      .startingLevel(100);
+  });
+
+  it("reduces Fire type damage by half", async () => {
+    await game.startBattle();
+
+    const enemy = game.scene.getEnemyPokemon()!;
+    const initialHP = 1000;
+    enemy.hp = initialHP;
+
+    game.doAttack(getMovePosition(game.scene, 0, Moves.FLAMETHROWER));
+    await game.phaseInterceptor.to(TurnEndPhase);
+    const heatproofDamage = initialHP - enemy.hp;
+
+    enemy.hp = initialHP;
+    game.override.enemyAbility(Abilities.BALL_FETCH);
+
+    game.doAttack(getMovePosition(game.scene, 0, Moves.FLAMETHROWER));
+    await game.phaseInterceptor.to(TurnEndPhase);
+    const regularDamage = initialHP - enemy.hp;
+
+    expect(heatproofDamage).toBeLessThanOrEqual((regularDamage / 2) + 1);
+    expect(heatproofDamage).toBeGreaterThanOrEqual((regularDamage / 2) - 1);
+  });
+
+  it("reduces Burn damage by half", async () => {
+    game.override
+      .enemyStatusEffect(StatusEffect.BURN)
+      .enemySpecies(Species.ABRA);
+    await game.startBattle();
+
+    const enemy = game.scene.getEnemyPokemon()!;
+
+    game.doAttack(getMovePosition(game.scene, 0, Moves.SPLASH));
+    await game.toNextTurn();
+
+    // Normal burn damage is /16
+    expect(enemy.hp).toBe(enemy.getMaxHp() - Math.floor(enemy.getMaxHp() / 32));
+  });
+});