Assault on the Control Room/Walkthrough

Usable

 * Pistol
 * Assault Rifle
 * Sniper Rifle
 * Rocket Launcher
 * Plasma Pistol
 * Plasma Rifle
 * Needler
 * Plasma Grenade
 * Fragmentation Grenade
 * M41 LAAG
 * Shade

Non-usable

 * Energy Sword

Vehicles
Early Banshee
 * Warthog
 * Scorpion
 * Ghost
 * Banshee
 * Wraith (non-drivable)
 * Pelican (non-drivable)
 * Spirit (non-drivable)

Equipment

 * Overshield
 * Health Pack
 * Active Camouflage

General Walkthrough
In the beginning of the level, as Foehammer will drop you off by the platform to the entrance of the control room, you will see Grunts running into the pressure doors to call upon their brethren. Now you have two options.

1) Board the Shade Turret and gun everything down.

2) Wait for the door to reopen and chuck a grenade over the oncoming crowds.

The first option is a little bit risky, because if you're playing on higher difficulties, the Grunts will always get on the turrets before you can even get close.

The second option is an immediate tactic that saves a lot of time, although the Elites may survive the blast. Swap a Plasma Pistol for the Assault Rifle for your next encounter. Venture into the short passage, the next room is littered with Grunts, but before that, you will have to take out the Elite. Use a charge shot to disable the Elites shield and gun him down with a pistol headshot. Fairly easy, but the Minor Elite may have spotted you, and he will began throwing a ridiculous amount of plasma grenades at you, lob a grenade at him to disperse the oncoming hoard of Grunts. Journey your way across the room, but don't get near the doors, because a hail of plasma by Jackals and Grunts will put you down. Lob another grenade at them, and proceed onto the bridge. The Bridge is one of the toughest parts in the level; with luck, you will lose only one or two health bars. Melee the Grunts with ease, do it swiftly, because they will wake up later on (thanks to fire team zulu's Pelican). Swap for the Needler over by the dead bodies. Again, you now have two options.

1) Walk down the second level and blast the Major Elite

2) Continue your way across the bridge.

The first tactic would be slow, but would guarantee a safer route throughout your journey.

The second tactic is quick, but will easily lead you into a situation where you find Grunts and Jackals surrounding you. All in all, you should succeed clearing your path with only pistol shots. Now I'll tell you what the Needler is for. Once you are at the end of the bridge, a Zealot with an Energy Sword will come running at you. These are absolute monsters, with grunts on their tails. Back away and fire rapidly at the Elite, stop and you're a dead man. There is an easier way though, throw a grenade to soften up the crowd, and take on the Zealot. Anyway, after a lot of killing, walk into the next room. This room is fairly easy to complete, with a few Stealth Elites and Grunts, take them out with pistol shots and swap for the Assault Rifle and health pack lying on the floor. Take them down to the basement. Now at the basement, you will encounter some sleeping grunts, melee them with ease, and proceed. You will soon find an Elite wandering aimlessly back and forth, melee him in the back or just chuck a grenade at him casually, this will certainly wake everyone up, even if you did the job stealthy, because someone on the other side will probably see you. Gun everyone down nice and clean and proceed into the snowy grounds. The snowy playground is quite a nasty place with Shade Turrets, far ahead; you will see Fire Team Zulu fighting with Jackals and an Elite. The Elite will start running towards the Ghosts parked underneath a small cliff top with a shade turret on it. Use your pistol to gun down the Grunt by your side and the Grunt on the cliff top, and proceed to the Elites. Beware of the Wraith's fire though; they're dead accurate at overturning vehicles. After you put down the Elite, swap for the Sniper Rifle or the Rocket launcher (Either one of them won't matter, you'll probably run out of ammo before you know it, you can swap the two weapons, which isn't recommended). Get onto the Warthog; drive it to the shady areas to pick up the Marines (in order to dodge the Wraith). Dash forward, you don't need to wait for the gunner (if you have one) to put down the aliens. You will eventually run into a crashed Pelican and meet the only Scorpion that's parked with Marines. Board the Scorpion and proceed. Again you have two choices:

(1) Take the route on your left or

(2) Kill the Ghosts on your right and proceed through the tunnel.

Both routes lead to the next area, but the first option would lead you into a state where you will be surrounded by Ghosts and Elites. The second option however, would lead you into a confrontation with a Wraith Tank. Anyway, clear the area and you will see a way down to your next destination. You can choose to eliminate the Wraith tank on top of the hills, but careful, a Banshee will come and fire plasma at you. Just keep your head down and go into the tunnel. Drive your way through with confidence, you wouldn't encounter any Grunts or Elites on your way but once you reach the end and see two Elites stop right there, you wouldn't want to alarm them of your presence. Wait till they were just a step from each other, and fire a Scorpion shell to finish them off. Drive your way into the vicinity. Now be careful, because this is always where people lose their health and steps, and their marines. The bridge is littered with Jackals, two Shade turrets could be a small threat on lower difficulties, but you would want to take them out beforehand on Legendary. A funny way of preventing the Grunts on boarding the shade is simply blast the turret into the pit. Now for the Jackals. On lower difficulties, they're just aliens walking with toy guns, but on Heroic or Legendary, they're devastating beasts. Before you get onto the bridge, blast the first group of Jackals. Continue on and you'll see the next pack of them. These guys hold charge bolts and can take down your shield with ease, coupled by a few blast from the Hunter at the end of the bridge. Put them down, and stop at the rear end of the bridge.

Easy/Normal Walkthrough (With Easy Way to Obtain the Early Banshee)
Foehammer drops you off. Run to the Shade she drops you beside. Shoot the Elite first, the turret should cut through his shields easily. Kill the Grunts that are on the platform, and beat down any in the halls. Pick up some Plasma Grenades, and move on.

Once you go through the hall, there will be an Elite marching back and forth. It will be almost impossible to assassinate him. Almost. Wait for him to walk next to the door's corner, run up, and whack him. If you do it too fast, he'll spot you. If you do it too slow, you'll find yourself face-to-face with him. So do it carefully. If you've succeeded, carefully creep towards the centre chasm, stay out of sight, and stick the Elite. Before it goes off, shoot as many of the Grunts with your Pistol as you can. If you didn't succeed in quietly killing the first Elite, just do a frontal assault. Once most of them are dead, a group of Jackals will come in. Seeing as you have UNSC weapons, just whack them.

When they're dead, go through the second hall. If you forgot which door you came through and which one you have to go through, check the arrows. On this level, they will point you on your way. Remember, in Two Betrayals, they will point in the opposite direction.

You're on the bridge. Look to your left and right, there should be some sleeping Grunts. Whack them, but stay out of sight. When a Pelican shows up, some Jackals will fire on them. Assassinate them as well. Going back to the door, look down to the lower level. If the Elite has his back turned to you, carefully walk down the ramp and melee him in the back. If not, stick him.

Stay on the lower level, walk through to the end, kill as many sleeping Grunts as you can.Go back up the ramp to the first level, and kill the Jackals. When you reach the end, shoot the Grunt (sometimes two) that occupy the Shade(s) with your Pistol. If you see the tall door opening, it means an Elite Zealot has arrived. The easiest way to kill him is to stick him. If he dodges it (he usually does, as higher-ranking Elites can leap around at physically extraordinary lengths) he will most likely jump off the bridge and die. If you stick him, keep your distance, because he has a powerful Energy Sword. When he's dead, go through the door.

When you enter the room, look to your left. There are some Grunts, and an invisible Elite that you won't see at first. Throw a few frags, they will kill them, and the Elite doesn't have shields. Finish off the survivors. There will be Grunts on platforms that will run back and forth. Crouch-jump onto a container, and then to the platform. Kill the Grunt on it, and walk to the center of the room. Staying on the platform, you will get a good view of the enemies below you and on the other three platforms. For the enemies further away, use your Pistol. For the ones closer to you, use the Assault Rifle. If you killed all of them, jump down, and you'll find a group of dead Marines and supplies nearby. Pick up some ammo, and finish off the enemies you couldn't kill. Go through the next hall, and up a short ramp. To your left will be an elevator lift. Walk onto it and activate the control mechanism.

When you reach the bottom, walk through the door. There will be sleeping Grunts to your left, right, and in front of you. Whack them all to death, and then turn left. There will be more, and kill them in the same way. Walk ahead, hide behind the weird containers. There will be an Elite walking away from you. Run up to him and whack him in the back. Keep going slowly, and there will be a Grunt on patrol, not seeing you. Beat him down, and there will be 2-4 sleeping Grunts on nearby elevations. Kill them all, and sometimes you can beat another one down. Now the room will have a few surviving Grunts, and Jackals. When you're absolutely sure you can't do any more quiet killing, aim at a Grunt (preferably a veteran), and shoot him in the head.

Now everyone knows you're here. Deal with the Jackals first, since they can drain your shields with a single shot. Use your AR either by looking for openings so you can shoot them, or whacking them. When they're dead, shoot down the Grunts, and walk through the door.

Now, you will have Marines with you for the first time this level. Shoot the Grunt in the Shade to your left (it always takes two shots), and take over. Aim the Shade at the other turret on the hill, and shoot at it. This gun is rather inaccurate, but I find I make more hits by aligning the top of the reticules circle with the enemy. When the Grunt dies, the Ghost will most likely turn its attention towards you. It shouldn't be too hard to destroy it with your turret. If there's some infantry that's noticed you, hose them with your turret. Get out, and join the Marines. You have a Wraith to deal with.

Pick up a Sniper Rifle and a Rocket Launcher (this is part of the Early Banshee trick), and see if you could pick off some distant enemies lurking near the sloping ridge before the short overhang. When you're done, jump in the 'Hog. Get some Marines on it, and charge the Wraith. This will be tricky, since some of the ground is ice, and unlike the Wraith, the Warthog does not hover, meaning traction will suck. But doing the best you can, keep the Warthog close to the tank's rear, where your gunner will have an accurate shot, and it can't shoot you. When it's exploded, drive towards the overhang, splatter the two Jackals there, and join the other Marines.

Ditch the Warthog and the tank. Since the machine gun is very inaccurate, it is advised to use it only in three situations:

One, if there’s only a Grunt or Jackal alive.

Two, if you or Marines are engaging them in close proximity.

And three, if there are enemy vehicles inbound that would pose a bigger threat. If any of those are the case, let your Marines take care of the infantry, and wait patiently for your next kill.

It is recommended to go down the bend rather than use the cave, since it gives you a better angle to tackle the first (well, technically second) Wraith. Blow up a few Ghosts as well, and shoot the Grunt gunner on the ridge off his turret. Leave your tank and walk up the ridge.

Making sure your Marines cover you so enemies don’t annoy you when you’re using your Sniper Rifle (which will make you zoom out), look at the platform where the future Pulse Generator is (for those who haven’t played Two Betrayals, look back to the bend, and look up) and zoom to 10x (8x for PC). You will see the Banshee’s top, which is a blur of magenta. Aim your Sniper Rifle at it, and without adjusting your aim, switch to your Rocket Launcher and fire.

If it impacts on the platform or wall, aim a little higher or lower (depending on where you missed), and try again. If you succeeded, good for you. The Banshee will most likely not fall, but will merely flip. This is all you need to do for now, as it will prevent the Elite from using it. Eliminate the remainder of the enemies, including the Wraith on the hill above the cave, and the Hunters in the cave.

Now, drive your tank to the right of the cave, where you will see a big boulder and a few supplies including active camouflage. Push the tank as close as you can to where the left side of the boulder meets the wall, and jump onto the tank. Crouch-jump onto the steep edge, and then on top of the boulder. Aim towards the second irregular steep edge, and crouch-jump. This may take a few tries, but you will make it up the hill where the remains of the Wraith is. Walk to the center, and you will have a straight and easy shot at the flipped Banshee. Look at it with your Sniper Rifle again, aim at one side of the Banshee, don’t move, switch to your Rocket Launcher, and fire.

The Banshee will fall to the inversion of whichever side you hit it at. You can switch either of your weapons for the other ones at the supplies if you want, but it doesn’t matter, because you won’t need to fire a single round from a weapon for the rest of the level.

Get to the Banshee, and fly it into the cave. Open the door, and fly in. You will be in a big cave filled with enemies, but never fear, for the sky’s the limit! (Or the top of the cave, anyway) Feel free to dispose of the enemies any way you want, but I’d recommend taking down those Hunters first, since their weapons can destroy your Banshee with a few direct hits. Interestingly, you can fly the Banshee into the bottom of the cave, and live.

When the enemies are all dead, open the second door, kill the enemies, and go up the giant tunnel. You see the Spirit dropship, but if you fly above it, its turret can’t hurt you. Wait for it to dispatch its troops, and kill them easily.

Fly further forward, and straight up. There will be another Banshee on a central platform, in perfect condition. If yours is damaged, you can switch it, but flip it over the edge just in case the Elite that will show up gets any ideas.

Take out the remaining enemies, starting with the Wraith, then the Ghosts, then the Hunters, then the Shades. Keep flying, and kill the enemies on the spiraling path. Fly down, kill the Hunters, and shoot the Shades as well.

Fly your Banshee over the cave rather than go through it, and no enemies will appear. Nor will any for the rest of the level. Fly for the twin bridges, go onto the one closest to where you came from, go through the door, pass a few empty rooms, and walk out onto the bridge. The Banshees will be there, but there will be no enemies. Fly for the pyramid, open a few doors, and you’re done!

Legendary Walkthrough
Before you start, remember this is Halo's longest level- not just in CE, but in the whole series. Confirm that you have enough time. Do conserve ammo. Never ever shoot the Elites straight forward with the pistol. Three clips is required just to drop a Blue Elite (Minor).

After you finished Silent Cartographer, you'll have a cutscene. After you get off, immediately chuck two grenades at the doors, as two Elites will come charging through, one a Major and the other a Minor. The grenades should extremely weaken the Major so use around half a magazine in a single burst to take it out before its shields can recharge. If you timed the grenades right, the Minor should be dead. If you receive a checkpoint too late after the doors have already begun opening, you might want to restart; this part is easily the hardest section in the whole level.

After the door closes and the Elites have been dealt with, get into the Shade and simply hold down the fire button at the door. Grunts will fall at your onslaught without any resistance. Take heed - be careful not too let a stray Grunt escape for two reasons. First, it will distract your fire, allowing other Grunts to surround you. More importantly, it will stick you, given the opportunity. By now, after clearing that part, you should have lost about one or two health bars. Proceed through the corridor and clear out the next room(s) by use of surprise/firepower. A hint to ponder: always kill silently until seen - the Major Elites can be extremely resilient, taking even a direct rocket in Legendary. Hey though, you wanted it! You might want to keep the Pistol, as it will help kill Grunts easily, and you will want it on the bridge. Ok, once you arrive at the bridge, you should quietly melee the Grunts to death. You will want to kill the Major Elite on the second level of the bridge. Even if no one sees you, Fire Team Zulu will arrive and wake everyone up. Try to kill the Major Elite, then man the Shade (preferably the one on the left-you get a better angle) and gun the Banshee down. Alternatively, you could use the Assault Rifle to destroy it. By now, you should also face the Jackals. Either use the Plasma Pistol, or get a plasma pistol and repeatedly overcharge it into the Jackals, depleting their shields. Do not charge; in three seconds is all it takes to kill you by a group of Jackals.

After you clear the bridge (it might take a long while-don't get frustrated!), the door should open and a group of Grunts, Jackals, and a Zealot should charge in. You can do this part of the level two ways, both of which will let you get past. First, simply spam the plasma or fragmentation grenades at the entrance. All the enemies should be eliminated in no time. Alternatively, you could kill the Jackals / Grunts with your Assault Rifle, and then challenge yourself by killing the Zealot with only the Assault Rifle. This is often considered a difficult task, as previous experience from the Truth and Reconciliation has shown. This time, you do not have the overpowered Sniper Rifle, complicating your task. Simply dodge or jump and you should emerge victorious. You could take advantage of its AI by simply going far enough. Simply go through the corridor, and you're in the next room. Take out the enemies (Grunts and Jackals). Then, you will see a Zealot with a plasma rifle. Quickly take it out with a combination of the Assault Rifle and grenades (Plasma Pistols also work in place of the grenades - just use the overcharge to bring down its shield).

The rest of the room, which consists of one or two Elites, should be dealt with easily enough. Proceed to the next room after reloading and stocking up on weapons. After fighting through a couple more rooms filled with Covenant, you should emerge onto the outside. First, you should be able to take the Grunt in the Shade with little problem, as he does not know you're there. Then, you can do one of two things:

(1) You can gun down the Ghost from your Shade. However, this causes the possibility that you will get hit by the Wraith which is bombarding Fire Team Zulu, or your Marines will all die before you arrive at their position. You do want a Marine gunner to help take out the Wraith.

(2) Alternatively, you could run towards the Marines' position and, with cover from the trees, avoid the Wraith while dealing with the Ghost and infantry. This will probably result in a lot of health, normally, so get in the gunner seat of the Warthog and gun the Ghost down.

(3) Simply grab the rocket and fire at the Wraith, Ghost, and infantry to simply clear the area. You may want to conserve the Rocket Launcher for later, however. If you adore the sniper, go ahead and grab it (while you're at it, snipe the Shade turret on top of the massive rock - it is sort of hard to reach otherwise). Get a gunner and passenger for your Warthog and drive on. A hint on taking down the Wraith: be careful of the ice. Once you're on the ice, you will stay in that direction and it may make you skid, making you an easy target. Remain on the ice, circle the Wraith, and the gunner will destroy the Wraith with ease.