Alien v.s. predator
You have to beat levels by accomplishing a goal and it must be on realistic or directors cut mode. After you get the cheat, you can find them in the main menu under cheat mode.
Alien episode 1
You must bite off ten live civilian heads. Then, you can use a weapon called Sniper Bite.
It let's you bite off heads from a REALLY long distance!
Alien episode 3
Fifteen dead civilian head bites. This cheat is very interesting. It's not just stick
figures, as you might believe, but actual pipe cleaners wrapped around for enemies.
Marine episode 1
Beat the level with at least 80% head shots. This gives you slow motion.
Marine episode 2
40% accuracy at least. This gives you 99 grenades in your pulse rifle. no bullets, and
cannot pick up any other gun.
Marine episode 3
Finish in under four minutes. This gives you warpspeed.
Marine episode 5
32 alien kills. All alien enemies start with a missing leg. They crawl around bleeding
leaving a trail behind them.
Predator episode 1
Get atleast 80% accuracy. (Use the shoulder cannon on the blue vision mode. It makes it
easier.) You get a mode called pigsticking. It makes the speargun have infinate ammo, and
has a shotgun like spread!
Predator episode 4
Must have atleast 40 Xenomorph kills. This cheat will make your enemies made out of
flames.