Complete each achievement to get the allotted gamerscore. The numbers between the () is the points given for each achievement.
| Achievement | How to unlock |
|---|
| Episode 1 | (Part 1) |
| Psycho (36) | Complete the game in Rorschach mode. |
| Hero (36) | Complete the game in Nite Owl mode. |
| Teamwork (36) | Complete the game in co-op mode. |
| Thief (15) | Find all abilities and pickups in Rorschach mode. |
| Detective (15) | Find all abilities and pickups in Nite Owl mode. |
| Untouchable (11) | Go unharmed for an entire level, without restarting from a checkpoint. |
| Turbo (11) | Complete the game in less than 80 minutes in one session, without restarting from a checkpoint. |
| Vigilante (8) | Eliminate 20 bad guys in 101 seconds. |
| Shield (8) | Dodge or block 25 incoming attacks. |
| Strong Arm (8) | Knock 100 people over, by throwing other people into them. |
| Retaliator (8) | Perform 200 counter attacks. |
| Exterminator (8) | Perform 250 finishing moves. |
| Episode 2 | (Part 2) |
| Morally Superior (36) | Complete the game as Nite Owl. |
| Street Justice (36) | Complete the game as Rorschach. |
| Friends Forever? (36) | Complete the game in Co-operative mode. |
| Martial Artist (15) | Perform all 8 Nite Owl combos within 60 seconds. |
| Feral Fighter (15) | Perform all 8 Rorschach combos within 60 seconds. |
| You Tag 'em - I Bag 'em (11) | Eliminate an enemy that your partner has knocked down or thrown in your direction. |
| Focus Fire (11) | Take down 10 enemies in a row finishing off each of them before doing damage to anybody else. |
| Electric Explosion (8) | Hit 14 enemies with a single electrify armor blast. |
| Rrarararghgh!!! (8) | Sustain a single rage mode for 60 seconds. |
| Ping Pong (8) | Hit at least 4 different enemies while building up a combo. |
| Unending Combo (8) | String a single uninterrupted combo that's at least 10 hits long. |
| Gentleman (8) | Complete Chapter III without hitting any ladies before they hit you. |
