diff --git a/public/audio/bgm/forest.mp3 b/public/audio/bgm/forest.mp3
index a1d9ecb4b28..6382d3fc0b2 100644
Binary files a/public/audio/bgm/forest.mp3 and b/public/audio/bgm/forest.mp3 differ
diff --git a/src/field/arena.ts b/src/field/arena.ts
index da74063ac06..afb202ecd23 100644
--- a/src/field/arena.ts
+++ b/src/field/arena.ts
@@ -707,7 +707,7 @@ export class Arena {
       case Biome.METROPOLIS:
         return 141.470;
       case Biome.FOREST:
-        return 4.294;
+        return 2.590;
       case Biome.SEA:
         return 0.024;
       case Biome.SWAMP: