Try to knock your opponent off the level before they knock you off!. Surely you've heard of the Nintendo 64 game Super Smash Bros. right? Well, Sonic Smash Brothers plays just like it where you have to knock your opponent off the stage with attacks that increase his damage meter. The higher his damage meter, the more likely he'll be knocked off the stage.
Arrows: Move - Up Arrow: Jump - Down Arrow: Crouch
Down Arrow + Space: Block - Shift: Pick up/Use - Backspace: Pause