Halo

If your going to use a plasma grenade, try throwing the grenade on the alien where it sticks onto them. It will blow up on them making sure it will kill the alien. Also the aliens can do this to you if you don't move.

If you are tiered of starting back checkpoints. Go to co-op and play one of the controlers this way you can run into a battle with no fear, because you will start right next to the second person every time.

On the Silent Cartographer level, after you unlock the door that leads to the map room, you will hear a call for help from a pelican under attack and inevitably crashes, leaving you a rocket launcher. The pelican crashes next to a butte with jackals on top. Drive a warthog on the catwalk (on the ocean side) that leads to the top, and drop down on the pelican. While still in the car, wedge yourself in the space between the cliff and the pelican until your practically sideways (with the tires facing the rock). Jump out, and you’ll be inside the pelican’s cockpit with an inside view of the control panel and all of the little details Bungie put in there.

On an elevator in any building built by the forerunners (i.e. Assault on the Control Room) walk backwards into the control panel. You will start to kind of go up and down furiously before going strait through the panel.

When this happens, immediately walk forward, towards the lift. If all goes well, you’ll sink halfway through the platform and be stuck. You can still look, aim, and shoot. You may have to try it a couple of times.

It’s more fun when you play with a friend because you can activate the lift and see your legs flailing around from under the platform.

When your fighting a hunter all you need is a pistol and one shot.(and a brain so you can aim). get up close so that he charges. When he does dodge the attack in any way that gets you behind him. Now take your time and aim the shot right into the orange flesh of his back. Fire and he goes BOOM! This really helps in legendary!

If you plan on taking the rocket launcher, which is the strongest ranged weapon in the game, be sure to have enough skill to handle it. This weapon isn't an easy weapon to use, and if used incorrectly, then you'll end up blowing yourself up. Make sure your shots are at quite close, and it is a medium-range weapon. If you fire this weapon at such a close range, you'll blow yourself up. Also, if you plan on taking out hunters, make sure you shoot their heads or bodies. If you shoot the shield you won't kill it in one shot. Also, this weapon can take out mostly any enemy, and it is great against the Flood. Use it to take out large swarms and concentrations of Flood, and also use it to take out Exploding Flood, which can bedestroyed easily by this weapon or a shotgun. The Rocket Launcher is also best used for taking out enemy vehicles, but since the rockets fly quite slowly, you'll have to aim carefully or you'll miss. The great thing about this weapon is that it has a 2x scope zoom, which allows more accurate targeting. If you want to take out a great group of strong enemies, aim for the ground around them. Even though the rocket won't hit anyone, the force will send them flying, which is one of the great things about the rocket launcher. This weapon also has a strong melee. Use this weapon and go take out some enemies!

On the second level when you are getting out of the ship. To your left there is a bridge and below it is another. Go to the right of it and there should be a crack. Slide down it slowly. It is just for fun.

Play "Assault on the Control Room". It doesn't matter what difficulty setting or if you are playing 1 or 2 player mode. Get to "If I only had a super weapon". Rush right ahead and ignore the Jackals and the first Elite. Instead, kill the second one as he is somind over the hill. Then run to the next one who is coming around the banshee. If you kill them both, the two banshees will be yours for the taking. I would suggest using the Plasma Rifle for killing them, as it stuns. You can use the 2 banshees for a banshee fight with a friend, too. Anyways. Ignore the enemies and do not go to the end of the bridge. Instead, go to the top of the hill that leads to the Control Room. There will be no Hunters, or aliens on the way up the hill! There will be the enemies that come out of the big door, though, but this shave's precious time off the level.

This will help if your annoyed by always having to go back because the yellow dude locks the door. First find a warthhog and get some people inside. Go where the place where there are lots of guys and where kortana says the covenant are putting up a real fight. Go down completely with your warthhog and go at full speed directly where the yellow dude is. If you did it right then your warthhog will be half way through. Press forward and get out. Then pass the level like you usually do and come back where the warthog is stuck. You may think it is impossible to get out but just press back and then get out. You will be in back of it and now you're done the hard part!

When playing split screen make your own game with human weapons only. Then add all vehicles and get rid of shields. Go to any level with a good sniping position. Get a sniper rifle and go there as soon as you can. Because the shields are off 1 shot to any where but the arms and legs instantly kills them. It's cheap but really fun to piss off all your friends!