Slap Happy Rhythm Busters is a 1-on-1 fighting game featuring a trendy Shibuya style and cel-shaded graphics reminiscent of Jet Set Radio. Despite the 3D graphics, it is strictly a 2D fighter. Certain specially moves, dubbed "Beat" moves, introduce a slight rhythm element: the player must hit certain buttons in time with the music to land attacks, and better timing will lead to more damage dealt.
Included are a single-player Arcade mode, a Versus mode, a training mode, and a special practice mode for the Beat attacks. There are 11 characters initially available, plus a further 10 unlockable through the Arcade mode.