Halo Cheats

1 shot kill
In multi-player, if you shoot any other player in the visor, your opponent will die automatically. This will work with most guns.
3 Guns
when the captian says "i dont keep it loaded"  run out, when you get to the corridor the Grunts will not be there not there so go went to the Cantiana get an alian gun then go back to where you saw the Captian, then leave to where there was the Grunts and there is where you get your other pistol which now make 3 GUNS!!!
a really neat trick with a tank and a ghost
on blood gulch park a tank in front of one of the bases but in bettween the post things and then get out get into the ghost and drive at the tank full speed,you will do a front flip onto the roof of the base leaving you a fantastic gun turret to blast those arms and legs off
active camouflague in a funny place
on 343 guilty spark, throw a lot of gernades when your in the pelican so that you don't get out. stay in there until the pelican lands. get out and walk to the right and border the clif edge. bordering the clif edge stil, walk to the right without falling off of the clif and you should see a medal tube below you. walk around it and jump down so that you are to the right of the tube. the active camouflague should be down there.
Alternate Ending Sequence
Complete the game in campaign mode on the legendary difficulty setting to view a different and longer ending sequence.
HIDDEN CAMOFLUGE
on the level swamp when you are about to go to the building there is a huge pipe to the side if you run up the hill in the corner is a camo: behind a tree
how to kill Hunters easily, even in 1 shot!
To kill Hunters you have to sneak up behind them and use a pistol, this works best with active camoflouge, the armour of hunter's have some empty areas in them ,the main ones head and back the one youre aiming for is the exposed skin on their backs using a pistol sneak up behind them and hit them dead center on their backs and they should die with one shot,if not then it takes a few shots, if u dont have active camoflouge,then get them to try and melee you with thier shield but doge it and they will run past you,quickly aim for ther backs and shoot , this happens in a split second so you have to be quick.