Complete the following achievements to unlock Xbox Live Gamerscore points.
Complete the indicated task to unlock the corresponding character.
Successfully complete all eight tournaments to unlock the Real difficulty.
Complete all eight tournaments, then replay any of the tournaments as the indicated character to unlock their concept art.
Complete all eight tournaments, then replay any of the tournaments as the indicated character to unlock their concept art.
Shoot all Secret Skullshots in all stages of a level to unlock the concept art for that level.
Kill 30 enemies in a level with a melee attack in either Tournament or Single Event.
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You can easily do this in the Steel Mill time-attack level "Time to Mill". Do this on Casual difficulty so you don't have to worry about your health.
Hit 5 Skullshots in a row (without killing a bad guy in between).
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Do this in Diagnosis Girder (4th event, Steel Mill)
1. Shoot skull in front of you
2. Turn left, go through the doorway and go downstairs. Find the next skull above the doorway in the bottom of the stairs
3. Take the corridor to the right. Find skull along the way.
4. After shooting #3, find another skull opposite of it.
5. Find the #4 near the end of the corridor.
At the end of Ghetto Blaster (first level of the stage 'Warehouse') there is a sign in front of the roof near the exit that says Clarke & Sons. Ltd. Shoot the other letters and leave only the letters S,O,S.