From the back of the box ...
A magical medieval playing field, rendered on the landscape of an overgrown chessboard, looms before you Within this mystical area are phoenixes, golems, and wizards. Like magical beings, their powers change as they move from square to square. When two opponents meet, the board explodes into a battlefield.
This game was a very successful EA title (this edition is released by Atari, but it is an "EA" game) because of the clever way that it blended strategy games with arcade elements. There were two sequels to the game.