diff --git a/src/arena.ts b/src/arena.ts
index 131c517cb06..c2aaa648f4c 100644
--- a/src/arena.ts
+++ b/src/arena.ts
@@ -102,7 +102,7 @@ export class Arena {
   }
 
   randomTrainerType(waveIndex: integer): TrainerType {
-    const isBoss = waveIndex > 10 && waveIndex % 20 === 10 && !!this.trainerPool[BiomePoolTier.BOSS].length
+    const isBoss = waveIndex > 20 && !(waveIndex % 30) && !!this.trainerPool[BiomePoolTier.BOSS].length
       && (this.biomeType !== Biome.END || this.scene.gameMode !== GameMode.ENDLESS || waveIndex % 250 === 0);
     const tierValue = Utils.randSeedInt(!isBoss ? 512 : 64);
     let tier = !isBoss
diff --git a/src/battle-scene.ts b/src/battle-scene.ts
index cd575faabe1..4e33e72c1b5 100644
--- a/src/battle-scene.ts
+++ b/src/battle-scene.ts
@@ -599,9 +599,9 @@ export default class BattleScene extends Phaser.Scene {
 				this.field.add(newTrainer);
 		} else {
 			if (battleType === undefined) {
-				if (newWaveIndex > 10 && newWaveIndex % 20 === 10)
+				if (newWaveIndex > 20 && !(newWaveIndex % 30))
 					newBattleType = BattleType.TRAINER;
-				else if (newWaveIndex % 10 !== 1) {
+				else if (newWaveIndex % 10 !== 1 && newWaveIndex % 10) {
 					const trainerChance = this.arena.getTrainerChance();
 					newBattleType = trainerChance && !Utils.randSeedInt(trainerChance) ? BattleType.TRAINER : BattleType.WILD;
 				} else