| Achievement | How to unlock |
| Electric Explosion (8 points) | Hit 14 enemies with a single electrify armor blast.
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| Friends Forever? (36 points) | Complete the game in Co-operative mode.
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| Feral Fighter (15 points) | Perform all 8 Rorschach combos within 60 seconds.
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| Focus Fire (11 points) | Take down 10 enemies in a row finishing off each of them before doing damage to anybody else.
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| Gentleman (8 points) | Complete Chapter III without hitting any ladies before they hit you.
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| Martial Artist (15 points) | Perform all 8 Nite Owl combos within 60 seconds.
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| Morally Superior (36 points) | Complete the game as Nite Owl.
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| Ping Pong (8 points) | Hit at least 4 different enemies while building up a combo.
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| Rrarararghgh!!! (8 points) | Sustain a single rage mode for 60 seconds.
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| Street Justice (36 points) | Complete the game as Rorschach.
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| Unending Combo (8 points) | String a single uninterrupted combo that's at least 10 hits long.
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| You Tag 'em - I Bag 'em (11 points) | Eliminate an enemy that your partner has knocked down or thrown in your direction.
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