Mario & Luigi: When Worlds Collide is the first Mario and Luigi RPG game for the Super Gamer. It introduces Wario and Waluigi to the RPG series. It takes place on an alternate Earth and starts in the normal Mario Earth Sarasaland, goes to alternate Sarasaland and ends in Alternate Mushroom Kingdom.
Wario and Waluigi are in a temple and find a glowing orb. Mario and Luigi come in and try to take the orb from Wario and Waluigi to return it. They drop it, it brakes and the two pairs of bros find themselves on and alternate Earth with good versions of the Wario bros and evil Mario Bros. They fight their way through together to get back home.
Beginning- Wario and Waluigi
World 1- Alternate Princess Daisy
World 2- Alternate Luigi
World 3- Alternate Mario
World 4- Alternate Professer E Gadd
Final Boss- Evil Demon God from the orb