Start a one player Co-op, 2 bots, with the following cheats: All guns, Unlimited ammo (NR is easier), and Cloaking device. If you do not have all guns, the Farsight Cheat should do. Select Pelagic II, agent, 2 bots. Kill the bots, activate your cloak, and head to where you find Elvis on Special Agent mode. You should come to a locked door, no matter. Pull out your trusty farsight and there should be a guy nearby a security camera; shoot NEAR him. He will run to the door and open it from the other side. Dispatch him or leave him standing. Now, proceed down the halls. Guards should be fighting not too far ahead, but strangely, they are BOTH red! If you decloak near them, they will stop fighting each other and shoot at you. See if you can guide the basement clan up to the Yellow halls and see how long they last.
Submitted by: AndyDark