Treasures
I don't see why anyone else has tried, but here are the treasures and the scenes they unlock during the credits:
Cactus-Cractus battle scene
Apple-Wario with apple trees
Fish-underwater Wario
Lamp-Wario and enemy
Lamp 2-Wario chased by enemy
Moon-Wario sleeping on the moon
Teddy-Wario and others as dolls
Lollipop-Wario at Doodle Woods
Gameboy Advanced-Wario with a box of GBAs
Robot-Wario at a shelf of toy robots
Rocking horse-one Wario band
We have more cheats and tips for this game here, Wario Land 4 cheats
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