Keyes (Level)

Looking for the Captain or his daughter?

Summary
Keyes is a campaign level in Halo 1. Once more, rescue Captain Keyes from inside the Truth and Reconciliation. This time, however, the ship is under attack from the Flood as well.

Usable Weapons

 * Pistol
 * Assault Rifle
 * Sniper Rifle
 * Shotgun
 * Frag Grenade
 * Plasma Pistol
 * Plasma Rifle
 * Needler
 * Plasma Grenade
 * Shade

Enemies Encountered in Easy difficulty and the hand-held weapons that they are known to use
Grunts

Elites
 * Minor- Plasma Pistol, Needler
 * Major- Plasma Pistol, Needler
 * SpecOps- Needler, Fuel Rod Gun (Not wieldable by player)


 * Minor- Plasma Rifle, Needler
 * Major- Plasma Rifle, Needler
 * SpecOps- Plasma Rifle, Needler
 * Ultra- Plasma Rifle (Dead corpses only)

Hunters


 * Rank N/A: Fuel Rod Gun (Attached to their armor)

Flood


 * Infection Form- Rank N/A: Weapons N/A
 * Carrier Form- Rank N/A: Weapons N/A
 * Combat Form (Elite)- Pistol, Assault Rifle, Shotgun, Sniper Rifle (Corpse seen near one, not actually used), Plasma Pistol, Plasma Rifle, Needler
 * Combat Form (Human)- Pistol, Assault Rifle, Shotgun, Plasma Pistol, Plasma Rifle, Needler

Note: The enemies encountered in this level along with the weapons that they wield is the same throughout all difficulty levels.

Part 01: Under New Management
''{Opening cinematic-Camera flies through a canyon filled with pools of reactor coolant, under a covenant cruiser. The cruiser is resting on the top of the canyon, apparently heavily damaged. Flood and Covenant forces are fighting all throughout the region.}''

Cortana: "The Covenant network is in absolute chaos! From what I've been able to piece together, their leadership ordered all ships to abandon Halo when they found the Flood, but they were too late. The Flood overwhelmed this cruiser and disabled it. The Covenant are terrified the Flood will repair the ship and use it to escape from Halo. They've sent in a strike team to neutralize the Flood and repair the ship for immediate departure. I've got a good lock on captain Keyes' CNI transponder signal! He's alive! And the implants are intact! There's some interference from the cruiser's damaged reactor. I'll bring us in as close as I can."

''{Master Chief teleports into the end of a corridor in the cruiser. The camera view flips over, upside down, and MC falls on his head; he was teleported in upside down.} ''

Cortana:"Ohh... I see! Coordinate data needs to be- "

{Master Chief bangs the side of his head with his fist as he stands up.}

Cortana:"Right. Sorry."

{After walking down the hallway several meters}

Captain Keyes (radio): "Chief... Don't... Be a fool... Leave me..."

Cortana: "Captain? Captain?! I've lost him."

{After getting to a hanger, with a large hole in the floor just past the door, blocking your progress}

Cortana: "Analyzing damage...This hole was caused by some kind of explosive. Very powerful if it tore through a ship's hull. All I detect down there are pools of coolant. We should continue our search somewhere else."

{After the staying in that corridor for a few moments, flood begin dropping out of a hole in the ceiling behind you, cutting you off.}

Cortana: "Warning! Threat level increasing!"

{After fighting off the increasing hoard of flood for a few more moments}

Cortana: "That jump into the coolant is looking better all the time, Chief!"

{After holding your ground longer}

Cortana: "Trust me! It's deep enough to cushion our fall!"

{After continuing to hold your ground}

Cortana: "Chief, we need to jump now!"

{Flood continue to pour out the hole, and from down the hallway, never ending, forcing you into the hole}

{After falling into the hole.}

''{Master Chief falls into a large pool of coolant, which breaks his fall. Camera view begins under-coolant. Covenant and flood are heavily engaged around the pool.}''

Cortana: "Lets get out of here, and find another way back aboard the ship."

{While walking down a narrow canyon}

Cortana: "We should head this way, towards the ship's gravity lift."

{continuing farther down the canyons}

Cortana: "The crash did more damage than I suspected. Analyzing. Coolant leakage rate is significant. The ship's reactor should already have gone critical."

{farther along in the canyons}

Cortana: "Power source detected. There's the gravity lift. It's still operational! That's our way back in!"

{once you take the gravity lift back inside the ship}

Part 02: Upstairs, Downstairs
Cortana: "We should be able to get into the ship's control room from here."

{upon finding an unlocked door}

Cortana: "The Covenant Battlenet is a mess. I can't access the ship's schematics. My records indicate that a shuttle bay should be... Here."

{Cortana marks the spot with a nav point}

{Upon reaching the nav point, it turns out to be a cargo bay}

Cortana: "Look, in the corners. The Flood are gathering bodies."

{Continuing on, entering a shuttle bay}

Cortana: "Looks like another shuttle bay. We should be able to reach the control room from the 3rd level."

Captain Keyes (radio): "I... gave you an order, soldier! Now pull out!"

Cortana: "He's delirious! In pain! We have to find him!"

{reaching the door on the 3rd level}

Cortana: "The control room should be... This way."

{She assigns another nav point}

{nearing the control room}

Part 03: The Captain
Captain Keyes (radio): "Waahhhh... Ahhhh ohhhh gaahhhhh..."

Cortana: "The captain! His vitals are fading! Please, Chief, hurry!" {once in the bridge of the cruiser}

''{A brain form sits on the command center in the bridge. The Captain's head sticks out of it, with his body dangling below, deformed.}''

Cortana: "No human lifesigns detected. The Captain! He's one of...them. We can't let the Flood get off this ring! You know what he'd expect... What he'd want us to do."

''{Master Chief punches into the Captain's head, sticking his hand inside. He pulls out the neural implants, shakes the Flood goo off of them, and puts them into his head.}''

Cortana: "It's done. I have the code. We should go. We need to get back to the Pillar of Autumn. Lets go back to the shuttle bay and find a ride."

{Once you reach the shuttle bay, a Covenant dropship enters the hanger, dropping off more troops, escorted by two Banshees}

Cortana: "Perfect. Grab one of the escort Banshees, and use it to return to the Pillar of Autumn. "

{Once you reach and get in a Banshee, Master Chief flies out of the hanger, being shot at by the covenant.}

Under New Management
Run ahead and laugh at the grunt being chased by an armless Flood. Gun them down then go back the way they came and you'll find some goodies. Grab the grenades, but don't get the active camouflage yet. It'll come in handy later. Move on down the path and you'll come across several grunts hanging out in the corridor. Move into the hall towards them then retreat. This will trigger a small group of Flood that will engage them, saving you the trouble. After the Flood have made a mess of them, come around the corner and finish everybody off with your assault rifle. Look ahead into the next hall and make sure there aren't any carriers lurking around. One of those Flood dropped a shotgun, so find it and make it yours, dropping your plasma pistol. Now you can head back and grab that active camouflage. Once you have it, run ahead, past the previous battle. Open the door and jump in the big hole. Whee!

You have just landed in the middle of a war zone. Fortunately, you're invisible. Creep out of the pool of coolant and take a look around. While you're invisible, feel free to wander around and toss grenades at any groups of Flood. Be careful of stray shots hitting you. This will make you momentarily visible, and then everyone will start shooting you. Eventually the Flood will overwhelm the Covenant and start looking for more stuff to kill. Right about then your invisibility should be wearing off. Run back into the pool of coolant you dropped into. Stay submerged and look out at the Flood on the shore. For some reason, this seems to confuse the Flood. They won't shoot at you from on shore and they only tend to come in after you in small groups. You can just blow these guys away with your shotgun when they get in the coolant with you. Once they stop coming, pop your head up and fire off a shell or two to get their attention. Duck back into the pool when things get too hot and shotgun anybody who comes in after you. After you've dealt with all the Flood you can see, hop out of the pool and scavenge through this area thoroughly. Turn on your flashlight to get a better look. You should find a pistol, which you should drop your assault rifle for. And there should be some more shotgun ammo lying around as well. Once you're set, find the path ahead and move out.

As you move along and on into the next battle or two, small groups of infection Flood will rain down on you from above. Keep an eye on your motion tracker and try not to get caught with your shield down. Anyway, more Covenant and Flood will be battling as you come to the next open area. They will be off to your left. Hang back and let them duke it out. You can spend the time sniping at the Flood on the ledge to the right. Once the battle is over, peek out and snipe at the remaining Flood on the left. There's a big rock leaning against the canyon wall to your left. Hide behind it when the Flood start charging you. Pump a shell into each one as they round the corner. Once they stop coming, move out into the area to scavenge. Stay frosty. Combat Flood will continue to drop down occasionally, and all the infection forms around tend to make the motion tracker all but useless. Once you're satisfied that you've scavenged everything usable and that no more Flood are going to show up, move ahead.

As you approach the narrow path ahead, a whole bunch of combat Flood will come out to greet you. Toss a grenade into the middle of them and shotgun each one as they come out to fight. After you go through what these guys drop, you should be just about full on shotgun ammo. Move along and keep an eye on your motion tracker. As soon as you see a big red blip, back up. Several carriers will drop down and explode. Deal with the infection forms and shotgun any combat forms lingering around. Move cautiously ahead until more blips appear on the tracker. Back up again and snipe any carriers with your pistol. Keep moving cautiously ahead and popping carriers until you get to a larger group of combat forms. By now the carriers will have stopped dropping on top of you, so you can move forward and deal with these guys up close and personal with your shotgun. Just past these guys you will find a health pack and a sniper rifle. The sniper rifle is almost completely useless against Flood, but it's great for watching the upcoming fight, so pick it up if you want.

Move ahead and grab some popcorn. You'll be here a while waiting for this battle to finish. Be careful. Occasionally a hunter will spot you and send a fuel rod your way, so don't get too comfy. You will also want to snipe any Flood hanging out on the land bridge. Use your pistol. The sniper rifle rounds pass right through Flood and do basically no damage. After all the Covenant have been killed, ditch the sniper rifle and dive into the melee. Shotgun anybody who gets in your way as you head under the land bridge. You should see two small pools of coolant off to the left with a health pack in between them. Head to the far side of the farthest pool. Stand your ground here and take out any carriers who hobble towards you. No more bad guys should spawn in the pools now, so move back out towards the middle of the area and finish off anyone still wandering around. Scavenge and head to the next area.

Next you will come to two grunts and an elite in a Shade. You really need to get in that Shade. And preferably before the many waves of Flood come pouring around the corner ahead. There are a couple of ways to get there. My favorite is to toss a plasma grenade behind the Shade. Try to get it as close to the Shade as possible, but on the far side. If you stick it to the Shade itself or the elite then this still might work depending on where it lands. All the Covenant will turn to look at the grenade so you can run up behind them and shotgun the two grunts. If the grenade goes off and blows the Shade towards you then you can hop in and immediately start whaling on the Flood. If it's too far away to affect the Shade, then you'll have to take out the elite with one or two point blank shotgun shells. Be sure to hit him and not the Shade. Then you can get in and start hosing down the Flood. Or you can wait until the first wave of Flood come around the corner and let the Covenant deal with them. They'll take out most of them before biting the bullet and then you can run in, clean up the Flood, and hop in the Shade in the brief lull between waves. Regardless of how you get there, once you're in the Shade, you should spin to face the corner the Flood are coming around and just hold down the trigger. Many, many Flood will come around that corner. Once they stop, try firing a few shots at the far wall of the canyon. That may trigger more to come down or you may have to get out and run around the corner. Once more Flood notice you, hightail it back to the Shade and start whaling on them again. Each time the Flood stop, there's probably more waiting around the corner. Eventually though, you will have exhausted their supply. Move around the corner and up the slope. As you near the top, you'll see a hole in the rock leading to the next area. As you approach, three more Flood will jump through. Blow them away then head back and scavenge before moving on. Remember there is probably a health pack still lying around in the previous area. Go back for it even if you don't really need it. We're about to pass another point of no return. This level seems to have a lot of those.

Drop down through the hole and follow the canyon to the next little skirmish. This one is pretty straightforward. Wait until the Flood have slain all the Covenant. Peek around the corner and get the attention of the Flood by blowing a few away with the pistol then step back and shotgun them as they come around after you. Move up when you're done and make sure all the Flood on the ground are dead before sniping the ones on the ledges with your pistol. Scavenge around and take note of the health pack for when you need it. Move past the battlefield cautiously. A mass of infection forms will appear on your motion tracker. They aren't much of a threat, but if you turn around and run back past the stationary shields and look in the coolant, you'll see what is. There's a whole crapload of carriers there just begging to be popped. Oblige them and clean up all the infection forms in the area. There are many, so you may want to temporarily requisition an assault rifle or something to mow them down. Once they're popped, move ahead.

This next fight is also fairly straightforward. You can't see much of the action from your angle, but a hell of a fight is going on under the gravlift. Eat some more of that popcorn while you wait and take note of the over shield at the base of the hill the Covenant are on. It's on the right. Once all the Covenant have been taken care of, move into the open a bit and get the attention of the Flood in the area. Stay near the entrance to the canyon where you've been hiding out and snipe them as they come for you. Fall back around the corner and shotgun them when they start to overwhelm you. Now you can move in and clear out the rest of the area. Once it has been cleansed, move up the ramp to the gravlift. A new wave of Flood will spawn behind you. If you stand your ground, you'll probably be whisked away before they can do much damage. However if you want to see to it that each and every one of them bites the big one then run straight through the gravlift, drop down on the other side, and head to your favorite hiding spot. Take out this wave the same way you did the last. No more stuff should spawn now, so take one last look around for ammo and infection forms then grab the over shield. Hang out under the gravlift to get whisked away to the Truth and Reconciliation.

Upstairs, Downstairs
You might get the jitters when you appear here, but don't worry. There really aren't any Covenant here this time. Just a few infection forms. Head out the door and down the hall. Carrier Flood will drop down in front of and behind you, so be careful. Just run past them or shoot them from a safe distance. If you stick around here, more carriers will continue to trickle down behind you, so don't worry about finishing off all the infection forms. Just keep moving.

Take a look down to the floors below. Eww. Big streaks of Covenant blood. And on the far right you'll see two health packs and an over shield. There are one or two Flood up here with you, so move ahead and take them down with your shotgun. They should have more shotgun ammo, so you can fill up. Take a moment to thin out the Flood below. You can snipe with your pistol or if they're right below you, you can use your shotgun. You could just drop down now and make a break for the next area, but don't you need more masochism in your life? Head into the halls and around a corner or two. A whole bunch of Flood are going to drop down from the ceiling here. Stay back around the last corner and shotgun them as they come after you. Retreat all the way back to the room with the bodies if you need to. Keep moving up and then retreating as you take out each wave. There are many, many Flood here, but eventually they will stop coming. The infection forms will continue to drop for some time however, so ignore them and move along.

Run up and shotgun any stragglers in the halls ahead until you get to the bottom floor. Look into the room and snipe any carriers ambling around. Move in a bit and you will trigger a new batch of Flood to come out of the big door near the over shield. Snipe a few with the pistol until they get uncomfortably close. Then back up into the hall and drop a grenade for them as they come after you. Shotgun the survivors. Now this place is yours. Move in and head to the far corner. Be careful not to pick up the over shield, but you should grab one of the two health packs now.

The way out is directly across from the way in. Head over to the door and move through with your shotgun at the ready. Just around the corner ahead is a nasty group of Flood. If they don't come after you immediately, you can peek around and blast one to get their attention. Drop a grenade and back up. Hammer them as they come around after you. They tend to come at you in two waves, so if there's a pause in the action, check your motion tracker. Bounce a frag grenade around the corner into the next group as they come out to play. Once the coast is clear, move around the corner. It's a dead end. You'll have to drop down that hole to proceed. Another one of those points of no return. Toss one of your weapons and pick up anything lying around. Crouch down and look through the hole for carriers to shoot. There are a few of them down there and its best not to drop down next to one. Take out the infection forms as well. Once you've killed everything within sight down there, grab your old weapon and head back for the other health pack and over shield. Grab these and drop down.

Finish off anyone left down here and move ahead. A battle will erupt ahead and you'll be stuck on the back end with the carriers. Blast them and pop the little guys. Move ahead but be careful not to provoke the Flood. You can peek around the corner and toss a grenade to help in the killing. And sometimes an elite will turn their back to you here or get close enough to shotgun to death. Once the battle is over, but before they can recover, run around the corner and pump a few shotgun shells into anything still moving. Duck back around the corner before they wear through your shield. Recharge and peer slowly around. Snipe any grunts and stick grenades to any elites. If you catch an elite alone, just run out and shotgun him at close range. After more of them go down, the last ones may retreat down the next hall and merge with another group of Covies down there. Move to the next corner and peer around. Toss a grenade right into the middle of them. When it goes off, run about half way down the hall and duck into the little indentation on the left. Blast anybody who comes up the hall to investigate. Peek out from here and snipe any grunts or toss another grenade. When there's only one elite left, run out and shotgun him. If they retreat out of sight, don't worry about them. They're about to die. Move to the end of hall, where it turns left, to trigger a big group of Flood to spawn behind you. If you were to turn around and head back up the hall they'd be on your right, but you probably shouldn't do that. They'll attack any remaining Covenant through another hall and once they engage, you can use the confusion to get the hell out of here. I hate to advise letting anything live, but there are just too many waves of Flood to deal with. It reminds me too much of The Library, and you've already passed that little test. If you want to stay, you can head back, wrap these guys around a corner, and shotgun them as usual. But be prepared to do that several times to exhaust the supply of Flood. Anyway, once the first group of Flood spawn behind you, take a right and watch out for a second group dropping down from the ceiling. Shotgun your way through them and head down the hall. Turn around and keep shooting as you back your way into the next area. By the time you get to the shuttle bay, they will have stopped coming.

As you enter the shuttle bay, there will be a health pack immediately on your left. You shouldn't need it now, but you probably will later. Don't forget about it. Duck down behind the stationary shield in front of you and take a look around. There are several elites running around on the central platform. Soon a group of Flood will attack them. Help the Flood out a bit by tossing a plasma grenade right into the middle of the elites. Be sure to catch the Shade in the blast if one of the elites has started using it. One well-placed grenade should be enough to put those elites in some serious trouble. Look to your left and you will see an open door that leads down to the bottom level. Occasionally reinforcements will come out of this door to help the elites on the central platform. Run in the door and shotgun any Covenant who rush out towards you. Move down the hall a bit until you come to another battle between Flood and Covenant. Don't engage them yet. You have to finish this battle first. The reason you came down here was to stop those reinforcements from spawning, so you don't have to worry about them anymore. Head back out to the shuttle bay. From here you have plenty of cover to work your way to the central platform. The elites tend to stay out on the platform, but any grunts hanging around tend to stay closer to the walkway you're on. Snipe them as you move towards the platform. Use the stationary shields and columns for cover. Peek out and toss plasma grenades into the middle of the elites. After each goes off, be prepared to run out and blow away any elites who had their shields knocked out but survived the blast. You can also pick up a needler if one is handy and spray them down with needles. After a bit of this, the elites should be in pretty bad shape. When there's only one or two left, you can run out onto the platform and hide behind the two computer box thingies on the right. From there you can peek out and grenade more, wear them down with shotgun blasts, or if you're patient they will often turn their back to you.

Now you have a choice. You can head back into the corridor leading down to the bottom level and clear out all of the nasty things in the hallways. Or you can turn around and continue on your merry way through the second level. I'm sure you hated having to let some Flood live a little while ago, so let's go kill everything.

Head back through the hall you went into before. Wait around until the Flood have all been killed. There will almost always be grunts and a hunter left here, so get your pistol out. Move around the corner and get the attention of the hunter. Get close enough to make him charge then back up. After he swings, plug him in the gut. You're in some pretty tight corridors here, so make sure you have space behind you to retreat. Behind the hunter will be several grunts. Bounce a frag grenade in if you have one to spare. Zoom in, peek around the corner, and put a bullet through each of the survivor's craniums.

Move around the next corner until you see Flood ahead then immediately retreat a bit. That should be sufficient to start the next battle going. Wait a moment then rush around the corner and down to the battle scene. Try not to divert the Flood's attention from the Covenant, but step out behind them and toss a grenade or two at the Covies. Once the grenades go off and the Flood are destroyed, peek around and snipe any grunts left alive. Once they're gone toss plasma grenades on or near any elites. Rush in and finish up with the shotgun if necessary. The last few Covenant will retreat down the hallway. Move up to the next corner and repeat. If you run out of plasma grenades, you can repeatedly peek out, fire off a shotgun shell, then duck back behind cover. You can wear them down this way, though it uses up a lot of ammo.

Move ahead once they're toast and out onto the floor of the shuttle bay. Explore a bit and take out the infection forms along with any bad guys that have fallen. Now at least you don't have to worry about falling down here and your motion tracker will be less cluttered. Move back through the hallways to the second level. Head past the central platform and through the door at the end of the bay on the left.

These next few battles are pretty simple. As you enter the hall, a few grunts up ahead will be attacked by various Flood. Retreat to the shuttle bay and stand to the side of the door. As grunts come running out, put them down with your shotgun. Once Flood start coming out, back up a bit and watch out for carriers. Finish off the Flood with a few more shotgun shells.

Head back into the hall, around the corner, and look about half way up the next hallway on the right. A section of wall has been peeled back and Flood like to get stuck in there. You'll probably have to go around and blast him from the other side. This will trigger the next batch of bad guys. More Flood fighting grunts. Retreat a bit and find some cover until the fighting stops. If the grunts win, snipe them or run in and shove your 8-gauge in their face. If the Flood win, snipe them then show them your 8-gauge when they run up in your face. If you're running low on pistol ammo, drop it here and pick up a plasma weapon. You don't really need it for the next battle.

Move ahead, take a right, and glance around the next corner to the left. There's a pile of Flood clogging up the hall and they're not leaving any time soon. Fire off a few pistol rounds or plasma shots to get their attention. Hang back and let the infection forms pop themselves on your shield. Recharge and look back around. These Flood will all stay put until you take a chunk out of them. So move around until you can see just the edge of one and blast him with your pistol or plasma weapon. If he runs towards you, back up and shotgun him. Keep whittling them down, taking on one at a time until you've finished them all off. Now you can run back for your pistol if you dropped it. Grab it and plunder what you can from the fresh bodies. There should be both shotgun and pistol ammo lying around. Move ahead and grab the health pack at the end of the hall if you need it.

A few seconds after you step out onto the third floor, a Covenant dropship will swing in and unload a squad of special forces. They'll drop down to the bottom floor, so you don't have to worry about them now. If you want to have some fun though, you can jump onto the dropship as it's flying in and then drop down onto the floor. You'll take some damage unless you time your crouch right. It can be an interesting challenge to try to take these guys out as they land. One of these grunts looks like they're holding a fuel rod gun, but doesn't actually have a weapon. If you're careful, you can take out everyone else and then watch him dance around threatening you with his nonexistent weapon. Good stuff.

Anyway, you can basically ignore these Covenant and just look to your right. Whip out your pistol and fire off a few shots at one of the Flood. This should get them pretty riled up, so toss a grenade towards them and duck back into the hall. Have a shotgun shell waiting for each one as they round the corner. Move back out and switch back to sniping with your pistol. Another wave will rush you so, so back up and get ready to put them down too. Snipe the last remaining Flood and move forward. When you approach the door, a new batch of Flood will come running through towards you. Toss a grenade just inside the doorway. You can move off to the right a bit and just blast these guys as they come through the door or you can retreat and spread them out a bit if you need to. Scavenge and move on.

The Captain
Keep going until you see a hell of a battle erupting ahead of you. Duck into the hall on the left and wait out the storm. There's a health pack tucked away in here, so grab it when you need to. After the initial firefight dies down, look around the corner. The Covenant tend to hang back at the end of the hall and the Flood tend to hang around in the control room. You will probably have to lure the Covies out of hiding to get the Flood to notice them. Run around, do a little dance, shoot at them, whatever it takes to get the Covenant to come down the hall after you and expose themselves to the Flood. Once there are only one or two Covenant left, you can take them out. Snipe them with your pistol as usual if they're grunts. If the elite is still around, you can stick a grenade to him or slowly wear him down with pistol or shotgun fire. Once the Covenant are out of the picture, it's all up to you. There are tons of Flood left in the control room, but you can whittle them down using the same tried and true techniques you honed on The Library. Peek out and fire off a few pistol rounds at one to get their attention, drop a grenade just around the corner, then back up and nail them with the shotgun as they come around the corner after you. If they start to over whelm you, don't be afraid to keep retreating as you fire. You can end up all the way back in the shuttle bay if you need to. Just keep pounding on them. Aim for carriers when you can. Scavenge and reload whenever there's a break in the action. Eventually they will all go down and your way will be clear. Look to your right as you enter the control room. There's another health pack there for when you need it. Move up the ramp to the center of the room to trigger the cutscene.

After you regain control, turn around and head to the bottom of the ramp. A massive group of Flood is about to come through the doors in front of you, and there's a pretty big group of Covenant waiting outside the door you used to enter. Walk up to that door. As you approach, it will open and two grunts will toss grenades into the control room. Right about now the Flood will be moving in. Make a break for the back of the room. With a little luck, the Flood will start attacking the Covenant and forget all about you. Stay behind one of the two pillars in the back of the room and wait out the battle. If you have any popcorn left, now would be the time to finish it. The Flood will win this battle. After they do, they tend to congregate around the base of the ramp that leads up to Keyes. Stay relatively close to the pillar in case you need to recharge behind it and snipe the surviving Flood with your pistol. Some may move behind a pillar out of sight. Finish off the easy ones then rush around the pillar and plug the last few with your shotgun. Scavenge as you head back to the shuttle bay.

Stop when you see a grunt being munched on by infection Flood. Just around the corner are a couple of combat Flood. Wait until they go out to fight the Covenant before moving into the next hallway. There are two groups of special forces that need to die before you can proceed. Each one consists of an elite and a few grunts with fuel rod guns and needlers. One is straight out the door and the other is around to the right. Keep an eye out for opportunities to stick bad guys with plasma grenades. The elite on the right in particular likes to get close and look out over the shuttle bay. Tag him if you can. This is the end of the level, so don't be afraid to use up your ammo. Take out the group straight ahead first. Peek out and snipe the grunts with your pistol. The elite can be frustrating. Run over to the right side of the doorway for him. Peek out and keep whittling down his shields with you pistol. He'll usually duck behind some boxes but leave just a bit of himself exposed. Aim carefully and keep shooting at whatever sliver you can see of him. If you just can't seem to get him, you can avoid his shots by crouching down and using the box turned on its side in front of you for cover. Now you can stay crouched and snipe at the grunts on the right. Once the grunts are taken care of, start picking away at the elite's shields. When he ducks for cover, rush in and pump a few shotgun shells into him to finish the job.

Now that that's taken care of, you have to get to the floor of the shuttle bay. You could head through the halls and eventually work your way down there. On the way, you would face innumerable Covenant and would probably wear both your thumbs to the bone trying to kill them all. Since there are just too many waves to plow through, I'll have to advocate the short and easy route. Stay on the third story and head all the way to the far right side of the shuttle bay. From here it's an easy drop down to the second level. Crouch when you land of course to minimize damage. Alternatively you could wait for the spirit dropship to dock and jump on that, then to the center on the second floor with no damage to your sheilds. From here you can hop down to the bottom floor easily enough. If you're quick, the Banshees won't even have landed yet (they may have if you used the dropship). When they come down, move out behind the one on the left. The pilot will hop out and you can be waiting right there behind him to bash his skull in. If you feel like it, you can walk over and bonk the other one as he gets out too. Pretty soon all hell will be breaking loose around here, so you'd better get in one of those Banshees and get the heck out of Dodge. Congratulations. You've almost beaten Halo on Legendary. Just one more level to go!

Trivia
In the cutscene where the Master Chief retrieves Captain Keyes' neural implants, the Master Chief was meant to burn Keyes' skull out of the Brain Form and retrieve the implants. However the final skull was said to be too gruesome to put into the game, so it was removed.

At the start of the level,look to your left,where a locked door is,look on the ground. You should see an Assault Rifle just standing there. You cannot take rounds from it or pick it up, so it must be inanimate. Also, if you look to your right,you will see a grating with Infection forms behind it trying to attack you. Go up to the grating and look behind the Infection forms. You should see Captain Keyes as a Brain Form.

When you get to Captain Keyes, look a bit to the right of the ramp and you should see one of Captain Keyes' tentacles. Sticking out of the tentacle is Captain Keyes' pipe.

If you shoot to one of the Energy Shield, desactivate it and stand over it and wait for the reactivation of it, you will blow away yourself, getting to the part of the Brain Form, and the Combat Forms will stay freezed.

It almost looks like the Brain Form has more than one body in it, you see another pair of de-formed legs and maybe a face or two. Eww...