While Wario was taking a ride in his private plane, the engine sputtered and he had to make an emergency landing. Taking refuge in a cave, he stumbles upon a magical music box. The box sucks him inside, where he comes across an odd fellow who claims to have been the ruler of the music box world. He cannot regain control until he finds five small music boxes. Wario agrees to help find the boxes in exchange for all of the treasure he can find and a ticket out of the music box. You take control of the invincible Wario as he travels throughout the kingdom. Even though Wario is invincible, enemies still pose a problem. When a bad guy hits him, Wario will be afflicted with some temporary effect. Utilizing these side effects is key to solving some of the game's more challenging puzzles. Help Wario find treasure and maybe a music box or two in WARIO LAND 3.

Source: game's box.