Streets of Rage 2 Cheats

Same Character in 2 Player
At the title screen hold [Right] and [B] on Controller 1 and hold [Left] and [A] on Controller 2. Press [C] on Controller 2 with everything else still held down. Now both players can be the same person in 2 Player!

Achievements
Complete each achievement to get the allotted gamerscore.

First Versus (10): Beat another player on Xbox Live in a versus match.
Fourth Boss (10): Beat the fourth boss.
Hard Win (35): Beat the game without using a special attack.
High Score (25): Score 800,000 points in one game -- with Game Settings set to Hardcore.
Kill Jet (30): Defeat Boss 'Jet' at the end of Stage 2 -- with Game Settings set to Hardcore.
Knife Wielder (5): Wield the knife in single player or co-op mode.
Online Co-op (10): Complete an online co-op game.
Online Warrior (5): Beat 10 opponents on Xbox Live in versus mode.
Perfect Boss (10): Beat the first boss without dying.
Perfect Win (40): Beat the game without continuing.
Pipe Wielder (5): Wield the pipe in single-player or co-op mode.
Psycho (15): Kill 10 enemies without losing your weapon.