Ok first go to the level where you meet the flood at any difficulty at the start your in the pelican keep holding down the backwards button if you jump out if the ship jump back in and hold down till the plane stops at another point this should be on the cliffs of the level.
1. Get out and face the way the pelican is.
2. Walk forward till you see a corner with a hill that you can't walk up.
3. Turn right and walk forward and eventually you will see a random marine standing there.

1. Go on legendary or heroic on the maw level.
2. When you get up to the bit just before you go in the room were your meant to blow up the ship you will see two arrows one says "engineneering" and "amoury" go the way the amoury arrow is points.
3. When you get inside the amoury you will see tons of rockets and shotguns. At the end of the room you will see a locked door.
4. Go towards it and then some invisible flood come out.

Hey Cody I told you I leave you a note here on the Halo cheat submit thing Hey if you neede help on a game I can help you to the best of my ability IF you have any questions you know where to find me OWOWOWOWOWOWOW!!!!!!

This glitch will make it so there are no covenant through the whole level

STEP 1 go on to co operative and go on to the level assault on the control room

STEP 2 once you go outside then jump off the bridge as close to the wall as possible and you will end up on a ledge

STEP 3 kill player two and then immediately jump off again and try to slide on the snow covered ledge near the bottom so that player two will come back to life on the ledge make him jump off and he should survive and then you will be at the bottom.
Look as hard as you can you won't find any covenant for the rest of the level
I know It works I try it every time

If an incoming enemy has thrown a plasma grenade at you, wait until the last moment, then throw your own plasma grenade. If done right, the other person's grenade will stick to yours and when it hits the enemy, they will be hit for TWICE the normal damage. Hey, it's more fun than dodging or letting it hit you!

On the levle Librarylook at the cxenter of the huge elevator and there will be a 4 leaf clover in the middle of the circle

Ok when you go 2 the first door that locks get you're plasma grenades and don't worry about the others cept the gold elite stick him and he will die but don't kill 1-2 of the grunts on you're way up they will b frozon on the ramp they will unfreze after cpt keys is done talking bibi

First of all this can only work on co-op.
Ok on the level Guilty Spark 343 there will be a cut scene at the beginning.
You and you start using the grenade button repeatedly and don't stop. Once you land the ship you will throw a grenade.Dont forget to have your partner to get out of the ship.
The grenade will cuase you to stay in your seat and not move.
When the Ship takes off you will still be in it feel free to now look around the level.
Below you will see covenant but if you shoot at them it will not work becuase your gun is pointing towards the ground.
Once the ship lands again have your partner through a grenade at the ground and kill himself he will respawn by you. Now have him kill you so you can get out to.You both are now outside the level stay near the edges and don't fall off the cliff area your on. If you walk far enough you will see a dead flood body lying on the ground. REmember you might not see him your first time cuase it's really foggy.
After that keep on walkingand evantually in the middle of no wear ther is a marine standing still but you can't kill him or move him he dosent even appear as green on you cross hair.
ENJOY THE ENDLES BOG signed: Shadowxxx

On the final level in the short cut tunnel that the front blows off of go through there and take the turn on your left behind a load of flud bodies is a random grunt who says somthing along the lines of: If we don't get off this ship soon we all going to be biiiiigggg space dust heeheee!!! Then he just sits there like a lemon following you with his head. Have fun with mister funky grunt!

You can actually kill a Hunter by beating the crap out of it with your gun.

Every one with the cheat for killing the flood with a shot from a shotgun,every knows that will work. I found out that no matter what, two shots from a human pistol will kill them.

NOTE:This doesn't work for plasma pistols.
When you need to reload go over to another gun then press x once to reload and before it finishes then HOLD x to swap your gun for the one on the ground. Your gun should continue reloading while it's on the ground. Then swap for it again and your gun will have the clip full but you won't have wasted anymore bullets.

On sidewinder on 2 player get a tank and put it by the teleporter on the mountain near the base with no bridge go to the left side and put the snow wall then get a ghost and ride up the tank and you will be on top of the level

One easy way to win a multi-player match is to use the 3 shot head kill.
It works with the pistal (UNSC or Human pistal).
When you get the pistal find some one and shoot them 3 times in the head to kill them (this works really well if you don't have the fancy stuff such as the rocket launchers, snipers, shotguns, ect.) It is a fun and easy way to win your opponets. Don't tell anyone who doesn't know how to use this trick and rack up the kills in your killing spree with the pistal (I would rank this one of my top 5 favorite weapons). Note:This also works on Halo 2.
Have fun and kill em all.

When you beat the level 343 guilty spark, watch the movie all the way.When it is almost over, you should see another floating blue light moving around, a second 343 guilty spark.

Have you ever noticed how many times srg. Johnson dies in this game?He dies on the Piller of Autumn & explodes on the Maw.There are more.

NOTE: must be in co-op
Go to any loading point(it wont work in some levels/i.e. Keyes/)where you can just walk back an forth and it keeps loading, now have one player charge a plasma pistol. After it starts shaking violently(about ten seconds)have the other player walk over the loading point(if it doesnt work you will know because it will still be shaking) but if it does work the pistol will stop shaking.Now release the trigger, your ammo will not deplete. Plasma weapons will still overheat(if they can) but will never run out of ammo.It works for any weapon(i like the rocket launcher >:P).
If you have any trouble (or have a question) e-mail me at padfoot_091@yahoo.com

step 1. Get a Scorpian tank set up for the way you wish to glide air for 10 seconds or more.
step 2. Grab a ghost and ride it over to the tank.
step 3. Drive the ghost towards any side of the scorpian tank.

DONE!

P.S Try to invent tricks like a grab, which you can do by exititng the ghost mid-air and getting back in fast. 3 times is the most I've got.

Try to beat my record if you dare!

(This cheat is mostly workful for needler) Go to the level with the beach and you land in sand because the pelican drops you off in there go to the spot where there is a door with a few grunts and a red guy I think its a hunter well before going in there hold your needler then run up and down the checkpoint 7x's (when your screen turns yellow and says checkpoint) Then shoot with your needler and see if when you reload if you still have all your carridges if this cheat doesnt work this may need a few more attempts.

While driving in a Ghost, hold A. This is fun when you drive off rocks you'll go flying!!!

This code is good to trick your friends. Drive the tank over where the portals go (Not where it goes to another portal but where you can't go back through it). Make sure its under the middle part of the tank and not near the sides or where the gunner is. Next take your guy back to where the portal is that u came through and go through it. If you do it right you will go through the tank but not in it.

If you take the other person and make them go in the tank (BUT DO NOT MOVE) You will see the guy get in the cage of the tank! If you make the Game type have Invisability He will not see u when ur under the tank. This is good to use if you ask your friends to start the game you just began so you'll be perfectly hidden while hes running around with her head loose! (Make sure u start his guy right where it usualy began). If your friend figures out where you are, you know he/she is cheating.

When you Get the Warthog through the door that the Elite with the Sword was make sure that you have two Marines in the back. Go through the part where there is a video very slowly and make sure the Warthog does not fly of the edge.

When you do this Master-Chief will die durring the Video While the Marines are still in the Warthog, Master-Chief will reapear, his old body will disapear and his ammo and everything will still be there, while your new guy still has all of the weapons and grenades.The Marines will be completely Frozen and The Aliens will not shoot at them!

PS: They will not come out of the Warthog when you ask them to!

Hey everyone. When you get back in the Cryo tube make sure you're standing up, when you're standing make sure you're facing inside the tube and wait for a check point.

Then press these combinations: up, then down and then A, X at the same time or Down, Up and A, X at the same time to either fall through the floor or get on the ceiling. If you get on the ceiling follow it untill you get to were those one guys die from the Elites.

Then jump on the lights, then jump on the other lights (or try to). You will be past the level but you won't be able to go on because instead of a locked door it is pitch black.

Hey everyone. If right when you get out of your cryo chamber jump right back in and Kneel down.Then Look at the chamber and you'll see Master-Chiefs Suit.(ps:If you keep kneeling down while looking up the chamber it will act like a latter.Then Keep trying to jump and you'll jump out of it or go through the wall!

On the Assault on the Control Room level, when you get the Scorpion, continue on through the small cave. When you leave the cave, there should be a small cliff. Look over that cliff and destroy the Covenant tank. After taking care of all the Covenant, ahead (To the right, I think) you should see a tunnel leading lower into the ground large enough for a vehicle *ahem* the Scorpion. It will save the checkpoint and from behind you, a Banshee will attack. Kill the Banshee. There are also two Hunters deeper in the tunnel guarding the Blast door. Kill them if you like but this is purely optional. (unless they are attacking you.) On top of the tunnel, there will be a small "mountain". On top of that mountain is another Covenant tank. If you haven't killed it already, then I suggest you should. Just move back and move on top of the snow hill surrounded by a few trees. Destroy it. Now, move toward the tunnel but to the right so the Scorpion touches the wall. Get out, and make your way up the mountain(Jump on the Scorpion and keep jumping your way up.) You'll be on top of the mountain and nearby the Covenant tank you just destroyed. Move further ahead and you should see the TADA! Floating Tree! Very bizarre glitch. Not used for anything much but eyecandy but you can "play" with it. If you crouch underneath it and look up, the wood disappears! Only leaving the leaves. You have now discovered one of the (maybe) many or few glitches of the game. Be proud of yourself =)

I figured out a way to have infinite ammo w/ any Earth-based weapon (Assult rifle, pistol, etc.), which works in between those long stretches depending on what weapons you have. To do this there needs to be another weapon laying on the ground; either Earth or Covenant doesn't matter. After emptying whats lef of your clip quickly pick the other weapon before Master Chief finshes reloading. Wait for about 5 to 7 seconds and pick up your orginal weapon completely reloaded without going into your clips. But note that this is a little bit harder to do with the shotgun due to the fact that it takes him a shorter time to reload.