Objective-Based These cheats can be used without being in debug mode, but it requires you to achieve a certain goal in every mission. The best way to get this cheat is make sure the civilians throw their Molotov cocktails away first, and don't hit themselves, then wait for them to cower and pick them off. This cheat is very fittingly named. The entire screen waves about, and will probably give you motion sickness before too long. This cheat is quite interesting.
Motion blur makes everything that moves, blurry.
John Woo Mode. There aren't very many aliens in this level, so this isn't too difficult. Be one with your gun and shoot with fine precision. Either that, or stick to your smartgun. The name pretty much says it all.