Battle the forces of evil and save the multiverse from the Dark Reaper Arcanon!

This side-scrolling brawler features 16 action-packed worlds inspired by Greek mythology. In story mode, Zeus, creator and ruler of the Guardians of the Gates, raises Antonius to go forth and defeat a new, unknown evil that has destroyed the Guardians and ravaged the universe.

To do so, Antonius must collect the Keys and Essence of each land. These will transform him into 13 different beasts with unnatural powers and special abilities -- hence the title, "Altered Beast."

Go solo or take on the Dark Reaper with a partner in the Co-Operative Mode. If you're feeling a little more aggressive, you and three friends can connect to battle each other and see who comes out on top. All the multiplayer modes require each player to have a Game Boy Advance, a Game Pak and a Game Boy Advance Game Link Cable.

Progress is saved to the game pak's memory.