The Rumble Fish 2 updates the original game with new gameplay mechanics and new characters. The offensive and defensive meters now go up to three levels each, with some supers now consuming differing numbers of bars. The new Boost Dive mode, which consumes one bar each of the players' offensive and defensive meters, temporarily places the character into a special mode with unique properties per-character. The new characters are:

-Sheryl, an assassin with a trap-based fighting style who attacks using wires.
-Mito, a girl who attacks using a bokken (wooden training sword).
-Bazoo, an enormous hulking man with long-range melee attacks.
-Lud, who fights using a gauntlet with a rushdown-oriented moveset.
-Hazama, the mid-boss, playable using a code.
-Beatrice, the boss, playable using a code.