Halo 2/Cairo Station

After testing out your new armor, follow the captain into an elevator and then into a tram that takes you into another cutscene. Once the cutscene's over, follow the Marines down the stairs to your left and you'll automatically pick up a Battle Rifle and an SMG. There are more guns back here, which is good to remember if you run out of ammo just a bit ahead—you can return here, grab another gun, and continue on your merry way. As you step into the recreation room, the Marines around you will start taking positions around the door at the end of the room. Stand guard by the door, and watch as it blasts out and a swarm of Covenant flood in. Clear 'em out, using their own weapons if necessary, and continue through the door and down the next hall. There are more Covenant here to slay—do the job, and run up the stairs just around the corner. At the top of the stairs is a room overlooking a courtyard with more Marines. Man the turret at the window, and shoot down the Covenant that come from the doorways to the right. Jump down through the window and into the courtyard, and proceed to the other end. There are more Covenant to deal with that'll creep out of the doors from both directions. When they're dealt with, follow the red arrow on the ground pointing to the hangar. Run up the stairs to enter the hangar, where you'll see a load of Covenant pour in through one of the windows just ahead. Jump down to their level to fight 'em face to face, and wait around a while after they're cleared out. Just after seeing one of your ships get obliterated in the distance, a new set of Covenant will come busting through the next doorway. Clear the hall, and continue through it to the next room. There are a few Marines holed up in the next room, with a few Covenant on a platform above pressuing them with turret fire. Rush under the turrets—you'll be able to avoid their fire if you run fast—and watch for the Covenant that come in through the hatch to the left. Take out the Elites first (a charged Plasma Pistol shot followed by SMG fire does the trick), and then focus on the Grunts. When the room's clear, you'll hear chatter of a bomb on board the ship. Locate the red arrow that leads to the MAC storage, and stand at the top of the stairway. You can see the feet of Covenant below—before taking fire on them, toss a grenade in the room if you've got one handy to soften 'em up. Run into the downstairs hall and continue your way into the next (there are some Grunts to deal with). When you reach the next room (through another door), watch out for some invisible Elites roaming the dark halls. The halls lead up to a new room (with two more Elites) with a Shotgun in the center. Pick it up if you know what's best for you. Be careful as you enter the next room. There are three plasma turrets being controlled by Grunts to watch for (one is on the ledge above, on the very far end of the room), along with a few Elites. Snipe out the turret controllers before approaching them, and they continue to lay waste to the room with your weapon of choice. There are narrow halls that border the room, giving you cover while you sneak closer in towards the enemies. When the room's cleared, follow the red arrow on the floor towards the Security room. As you enter the doorway you'll take fire from another plasma turret to your right. Snipe out the grunt in control of it, and run up the stairs behind him. More Covenant rush in the room as you enter—clear them out, and continue down the halls until you meet up with more Marines. Clear the hall, and enter one of the hatches with the red arrow pointing to Umbilicals. Two Elites equipped with jet packs enter the room as you do. Rush them with your Shotgun if you've got it, and jump out the door to land on the platform outside. Follow the red arrow towards Shipping, and shoot down the two flying Elite you meet on your way. The next hall opens up to large elevator room—imediately as you enter, flying Covenant swarm up in front of you. Shoot them down with your Battle Rifle or SMG, and immediately step to the ledge ahead. The elevator below is slowly coming your way, and it's not coming alone. Snipe out as many Covenant as you can before the elevator reaches your level, and then jump onto the platform to finish the job. Take the elevator back down (the controls are on the top level), and as you step off snipe down the three flying Elites at the other end of the outdoor walkway. Continue across the metal structures and enter the elevator to head to Firing Control. Once the elevator has stopped, get ready for some fancy shooting. There are three or four Elites standing around the bomb in the room. Clear 'em out (it's safe to use grenades around the bomb—promise) to initiate another cutscene that leaves you off back at Earth.