This is a list of custom music used in Wario Land 4: Parallel World.
Most of them are from other games' OST.

[Sound Room]
Not Playing CD: Earthbound - File Select

Emerald Passage CD
Level 1: Wario Blast - Forest Zone
Level 2: Kirby's Dream Land 3 - Ripple Field 2
Level 3: Super Mario 64 - Dire Dire Docks
Level 4: Chrono Trigger - Corridors of Time

Ruby Passage CD
Level 1: Super Mario Land 2 - Wario's Castle
Level 2: Undertale - Ruins
Level 3: Romancing SaGa 3 - Podorui
Level 4: Mario Kart DS - Waluigi Pinball

Topaz Passage CD
Level 1: Mario's Super Picross - Mario BGM 2
Level 2: t[BGM DOVA-SYNDROME - ʂ̖`
Level 3: Wario's Woods - Round Game
Level 4: Kururin Paradise - Neo Land

Sapphire Passage CD
Level 1: Madou Monogatari ARS - Temporal Temple
Level 2: Wario Ware DIY Ashley's Records - Rainbow-bot
Level 3: Earthbound - Kraken of the Sea
Level 4: Super Mario RPG - Fight Against Smithy, Who Likes Transforming

Karaoke: Bomber King Theme Song

[Level]
Secret Bonus Room: Super Mario Sunshine - Secret Area

Emerald Passage
Level 4: Wario Land3 - ForestOfFear

Ruby Passage
Level 1: Wario Land 2 - Factory

Golden Passage
Level 1: Wario Land 2 - The Really Final Chapter

[Misc]
Title: Wario Land 3 - Title
Map  : Cave Story - Geothermal
Shop : UnderTale - Shop
