Get evil Karma Early
On the mission escape the Neon by the bridge (I don't know the real mission but it is right after the food mission where you get to fight reapers for the first time) you need to do two things.
1 want to be evil and have evil Karma.
2 beat the police by the riot and get through the first section but don't open the gate after it right away.
After you have that start shooting anyone other than your friend You will get bad karma and they never die so blast and wait till they get up (about 3-10 seconds) you can do this until your done or it gives you no more Karma.
Added by: fox demon Dec 19th 2009, ID#2257