diff --git a/src/game-mode.ts b/src/game-mode.ts
index e543e3c42ca..508957575c5 100644
--- a/src/game-mode.ts
+++ b/src/game-mode.ts
@@ -331,7 +331,7 @@ export class GameMode implements GameModeConfig {
    * @param waveIndex The wave to check.
    * @returns The fixed battle for this wave.
    */
-  getFixedBattle(waveIndex: number): FixedBattleConfig {
+  getFixedBattle(waveIndex: number): FixedBattleConfig | undefined {
     const challengeConfig = new FixedBattleConfig();
     if (applyChallenges(ChallengeType.FIXED_BATTLES, waveIndex, challengeConfig)) {
       return challengeConfig;
diff --git a/src/phases/select-biome-phase.ts b/src/phases/select-biome-phase.ts
index 21c0cfade94..2117cd09c18 100644
--- a/src/phases/select-biome-phase.ts
+++ b/src/phases/select-biome-phase.ts
@@ -33,9 +33,7 @@ export class SelectBiomePhase extends BattlePhase {
             "SelectModifierPhase",
             undefined,
             undefined,
-            gameMode.isFixedBattle(currentWaveIndex)
-              ? gameMode.getFixedBattle(currentWaveIndex).customModifierRewardSettings
-              : undefined,
+            gameMode.getFixedBattle(currentWaveIndex)?.customModifierRewardSettings,
           );
         }
       }
diff --git a/src/phases/victory-phase.ts b/src/phases/victory-phase.ts
index ac567cc99c5..4bafa28d97c 100644
--- a/src/phases/victory-phase.ts
+++ b/src/phases/victory-phase.ts
@@ -71,9 +71,7 @@ export class VictoryPhase extends PokemonPhase {
             "SelectModifierPhase",
             undefined,
             undefined,
-            gameMode.isFixedBattle(currentWaveIndex)
-              ? gameMode.getFixedBattle(currentWaveIndex).customModifierRewardSettings
-              : undefined,
+            gameMode.getFixedBattle(currentWaveIndex)?.customModifierRewardSettings,
           );
         } else if (gameMode.isDaily) {
           globalScene.phaseManager.pushNew("ModifierRewardPhase", modifierTypes.EXP_CHARM);