diff --git a/src/field/pokemon.ts b/src/field/pokemon.ts
index 96cc9cd6562..006b15eace3 100644
--- a/src/field/pokemon.ts
+++ b/src/field/pokemon.ts
@@ -4746,7 +4746,7 @@ export class EnemyPokemon extends Pokemon {
       undefined, dataSource ? dataSource.nature : undefined, dataSource);
 
     this.trainerSlot = trainerSlot;
-    this.initialTeamIndex = globalScene.currentBattle.enemyParty.length;
+    this.initialTeamIndex = globalScene.currentBattle?.enemyParty.length ?? 0;
     this.isPopulatedFromDataSource = !!dataSource; // if a dataSource is provided, then it was populated from dataSource
     if (boss) {
       this.setBoss(boss, dataSource?.bossSegments);
diff --git a/src/test/moves/effectiveness.test.ts b/src/test/moves/effectiveness.test.ts
index fddeb1ac790..a5bd343da09 100644
--- a/src/test/moves/effectiveness.test.ts
+++ b/src/test/moves/effectiveness.test.ts
@@ -6,7 +6,6 @@ import { Abilities } from "#app/enums/abilities";
 import { Moves } from "#app/enums/moves";
 import { Species } from "#app/enums/species";
 import * as Messages from "#app/messages";
-import { overrideHeldItems } from "#app/modifier/modifier";
 import GameManager from "#test/utils/gameManager";
 import Phaser from "phaser";
 import { afterEach, beforeAll, describe, expect, it, vi } from "vitest";
@@ -15,15 +14,14 @@ function testMoveEffectiveness(game: GameManager, move: Moves, targetSpecies: Sp
   expected: number, targetAbility: Abilities = Abilities.BALL_FETCH, teraType?: Type): void {
   // Suppress getPokemonNameWithAffix because it calls on a null battle spec
   vi.spyOn(Messages, "getPokemonNameWithAffix").mockReturnValue("");
-  game.override
-    .enemyAbility(targetAbility)
-    .enemyHeldItems([{ name:"TERA_SHARD", type: teraType }]);
+  game.override.enemyAbility(targetAbility);
 
   const user = game.scene.addPlayerPokemon(getPokemonSpecies(Species.SNORLAX), 5);
   const target = game.scene.addEnemyPokemon(getPokemonSpecies(targetSpecies), 5, TrainerSlot.NONE);
 
   if (teraType !== undefined) {
-    overrideHeldItems(target, false);
+    target.teraType = teraType;
+    target.isTerastallized = true;
   }
 
   expect(target.getMoveEffectiveness(user, allMoves[move])).toBe(expected);