Implement stellar tera damage boost

src/data/move.ts

@@ -4918,6 +4918,30 @@ export class TeraBlastTypeAttr extends VariableMoveTypeAttr {
   }
 }
 
+/**
+ * Attribute used for Tera Starstorm that changes the move type to Stellar
+ * @extends VariableMoveTypeAttr
+ */
+export class TeraStarstormTypeAttr extends VariableMoveTypeAttr {
+  /**
+   *
+   * @param user the {@linkcode Pokemon} using the move
+   * @param target n/a
+   * @param move n/a
+   * @param args[0] {@linkcode Utils.NumberHolder} the move type
+   * @returns `true` if the move type is changed to {@linkcode Type.STELLAR}, `false` otherwise
+   */
+  override apply(user: Pokemon, target: Pokemon, move: Move, args: any[]): boolean {
+    if (user.isTerastallized && user.hasSpecies(Species.TERAPAGOS)) {
+      const moveType = args[0] as Utils.NumberHolder;
+
+      moveType.value = Type.STELLAR;
+      return true;
+    }
+    return false;
+  }
+}
+
 export class MatchUserTypeAttr extends VariableMoveTypeAttr {
   apply(user: Pokemon, target: Pokemon, move: Move, args: any[]): boolean {
     const moveType = args[0];
@@ -11078,6 +11102,7 @@ export function initMoves() {
       .chargeAttr(WeatherInstantChargeAttr, [ WeatherType.RAIN, WeatherType.HEAVY_RAIN ]),
     new AttackMove(Moves.TERA_STARSTORM, Type.NORMAL, MoveCategory.SPECIAL, 120, 100, 5, -1, 0, 9)
       .attr(TeraMoveCategoryAttr)
+      .attr(TeraStarstormTypeAttr)
       .attr(VariableTargetAttr, (user, target, move) => user.hasSpecies(Species.TERAPAGOS) && user.isTerastallized ? MoveTarget.ALL_NEAR_ENEMIES : MoveTarget.NEAR_OTHER)
       .partial(), /** Does not ignore abilities that affect stats, relevant in determining the move's category {@see TeraMoveCategoryAttr} */
     new AttackMove(Moves.FICKLE_BEAM, Type.DRAGON, MoveCategory.SPECIAL, 80, 100, 5, 30, 0, 9)

src/field/pokemon.ts

@@ -132,6 +132,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
   public evoCounter: number;
   public teraType: Type;
   public isTerastallized: boolean;
+  public stellarTypesBoosted: Type[];
 
   public fusionSpecies: PokemonSpecies | null;
   public fusionFormIndex: number;
@@ -244,6 +245,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
       this.customPokemonData = new CustomPokemonData(dataSource.customPokemonData);
       this.teraType = dataSource.teraType;
       this.isTerastallized = dataSource.isTerastallized;
+      this.stellarTypesBoosted = dataSource.stellarTypesBoosted;
     } else {
       this.id = Utils.randSeedInt(4294967296);
       this.ivs = ivs || Utils.getIvsFromId(this.id);
@@ -295,6 +297,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
 
       this.teraType = Utils.randSeedItem(this.getTypes(false, false, true));
       this.isTerastallized = false;
+      this.stellarTypesBoosted = [];
     }
 
     this.generateName();
@@ -2759,11 +2762,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
     const matchesSourceType = sourceTypes.includes(moveType);
     /** A damage multiplier for when the attack is of the attacker's type and/or Tera type. */
     const stabMultiplier = new Utils.NumberHolder(1);
-    if (matchesSourceType) {
-      stabMultiplier.value += 0.5;
-    }
-    applyMoveAttrs(CombinedPledgeStabBoostAttr, source, this, move, stabMultiplier);
-    if (source.isTerastallized && sourceTeraType === moveType) {
+    if (matchesSourceType && moveType !== Type.STELLAR) {
       stabMultiplier.value += 0.5;
     }
 
@@ -2771,6 +2770,20 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
       applyAbAttrs(StabBoostAbAttr, source, null, simulated, stabMultiplier);
     }
 
+    applyMoveAttrs(CombinedPledgeStabBoostAttr, source, this, move, stabMultiplier);
+
+    if (source.isTerastallized && sourceTeraType === moveType && moveType !== Type.STELLAR) {
+      stabMultiplier.value += 0.5;
+    }
+
+    if (source.isTerastallized && source.teraType === Type.STELLAR && (!source.stellarTypesBoosted.includes(moveType) || source.hasSpecies(Species.TERAPAGOS))) {
+      if (matchesSourceType) {
+        stabMultiplier.value += 0.5;
+      } else {
+        stabMultiplier.value += 0.2;
+      }
+    }
+
     stabMultiplier.value = Math.min(stabMultiplier.value, 2.25);
 
     /** Halves damage if the attacker is using a physical attack while burned */
@@ -3808,6 +3821,7 @@ export default abstract class Pokemon extends Phaser.GameObjects.Container {
   resetTera(): void {
     const wasTerastallized = this.isTerastallized;
     this.isTerastallized = false;
+    this.stellarTypesBoosted = [];
     if (wasTerastallized) {
       this.updateSpritePipelineData();
       globalScene.triggerPokemonFormChange(this, SpeciesFormChangeLapseTeraTrigger);

src/phases/move-effect-phase.ts

@@ -390,6 +390,12 @@ export class MoveEffectPhase extends PokemonPhase {
               target.lapseTag(BattlerTagType.SUBSTITUTE);
             }
           });
+
+          const moveType = user.getMoveType(move, true);
+          if (move.category !== MoveCategory.STATUS && !user.stellarTypesBoosted.includes(moveType)) {
+            user.stellarTypesBoosted.push(moveType);
+          }
+
           this.end();
         });
       });

src/system/pokemon-data.ts

@@ -48,6 +48,7 @@ export default class PokemonData {
   public evoCounter: number;
   public teraType: Type;
   public isTerastallized: boolean;
+  public stellarTypesBoosted: Type[];
 
   public fusionSpecies: Species;
   public fusionFormIndex: number;
@@ -108,6 +109,7 @@ export default class PokemonData {
     this.pokerus = !!source.pokerus;
     this.teraType = (source.teraType || 0) as Type;
     this.isTerastallized = source.isTerastallized || false;
+    this.stellarTypesBoosted = source.stellarTypesBoosted || [];
 
     this.fusionSpecies = sourcePokemon ? sourcePokemon.fusionSpecies?.speciesId : source.fusionSpecies;
     this.fusionFormIndex = source.fusionFormIndex;