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Part 01: Oh, So That's How it is?
The level starts the player off at the top of a cliff with a Plasma Rifle. Walk through the path to meet the corpse of an Elite and an Energy Sword lying next to it. Strafe over it to pick up the Energy Sword and a few grenades. Continue on and there will be a few Brutes which are easily killed with the Energy Sword. The pathway continues to be infested with Brutes. Camouflage, lunge-kill the Minor Brute from behind, then move forward and attack the pair. More Brutes will advance, so take cover and use any available Plasma Grenades. When available, swap the Plasma Rifle for a Brute Shot.
Continue up the hill, killing any Brutes on the path with the Brute Shot. Midway along the path, a Spec-ops Elite with an Energy Sword will assist in taking out the Brutes. After they are all dead, a set of pods will open with three Elites. There will be two Minor Elites with Plasma Rifles. Give one of them a Brute Shot for support.
Follow the Elite that helped kill the Brutes into a room. The room will lead you into another full of allied Grunts, enemy Drones, Jackals, and Brutes. Use grenades and the Brute Shot to kill all enemies on the first level. The Brute Shot is a formidable melee weapon so it may be worth keeping even if it's out of ammo.
Find a ramp to the second level. Kill all the enemies here. Consider swapping an empty Energy Sword for a Brute Plasma Rifle when available. Go up the ramp that leads to a door guarded by Drones and Brutes. Take care of them with the Brute Plasma Rifle or Brute Shot. Enter through the door.
Below should be some Brutes and Jackals. Take them out with the Brute Plasma Rifle, Brute Shot, or grenades. Take care when using grenades around the Zealot; he dies easily when hit with a grenade. Continue through two doors which will lead into a room with several ledges. A small force consisting of Jackals and Brutes is waiting below. On the left side of the first ledge are two Power Cores along with a weapon holder. If you stand somewhat left of center between the Cores, face very slightly from the right of center between the cores and then melee the upper part, you can knock both of them down, with one heading for the Jackals far from you and the other careening to the Methane Tank and other Jackals right below you. This results in a spectacular explosion and wipes out all the Jackals on the ledge. After that, toss grenades down or use the Brute Plasma Rifle to lay waste any stragglers remaining.
Jump down and face the Brutes. It is more effective using a Brute Shot melee than Brute Plasma Rifle bursts. Jump down again and take out all Brutes there. Once they lie dead, a second wave of Brutes will come out of the door. Be sure to pick up any available Brute Shot ammo.
Head inside the door and replace your Brute Plasma Rifle with an Energy Sword lying on the dead corpses of the Elites. Continue through the doorway to find several Jackals and Brutes, one of which is manning a turret. Camouflage and take out the Brute on the turret with a Plasma Grenade or Energy Sword, and the man the turret. Kill the other enemies with the Energy Sword or Brute Shot. Continue through the room and pickup a Fuel Rod Gun with extra ammo available behind a crate.
Part 02: Step Aside...Let the Man Go Through!
Quickly reload the Fuel Rod Gun and walk through the door. Do not give your Fuel Rod Gun to any allies whatsoever. Shoot the Brute on the right, then quickly shoot the Brute on the left because your ally Zealot will always head toward the right first or there may be an ally suicide. If your Fuel Rod Gun did not deal with the Brutes or Jackals don't worry, your allies will. Go down the pathway. A Brute Captain will now get off his Ghost and try to shoot you with his Brute Shot. Behind him, some of his allies will come. It`s a good idea to hijack the Ghost and kill them. Try and destroy them as soon as possible, because, if not, it could mean the end for an abundance of your allies.
If you didn't hijack the Ghost, there two more in the cave. Get on the Ghost and go through the cave. It might be hard here because of the darkness, but, don't worry, you'll make your way through.
When you get out of the cave, in front of you will be some enemy Brutes and Jackals. Look to your right, there should be a Brute on a Shielded Plasma Turret. Ram into him with your Ghost, he'll die. Your allies should be following you by now, helping you destroy all enemies. Ram into the rest of the enemies, or shoot them, making sure that you do not harm your allies, as you might need them for help at the end. At this point, a few Minor Grunts may die; don't worry, it's expected.
When all the Jackals and Brutes are dead, turn around into the cave where you came from, there should be one or two waves of Jackals. You can let your allies take care of them, or you could alternatively get off your Ghost and mow them down with the Energy Sword. At this point, your Energy Sword might be out of ammo. If not, keep using it. If it is, swap your out-of-ammo Energy Sword for the Brute Shot somewhere around where you are, and hop back on your Ghost.
Go down the ramp; it leads to another place similar to where you were just fighting. Kill all the enemies there, it's straightforward. Midway through, a Spectre with two Brutes (one driver, one on the turret) will come. If you are on the cliff with the turret, take the Type-50 particle beam rifle and snipe the Spectre driver, then the Brute that's commanding the turret. If you couldn't snipe the Spectre driver, you can take it over by hopping on the Spectre twice, or three to four times if a Brute hops back on, or alternatively kill it with your Ghost and carry on.
Go down the ramp again, some Brutes might be hiding. You can ram them with your Ghost, or if you took control of the Spectre wait for an ally Elite to get in. Just carry on and let your allies kill them. Don't fret, your allies can stand enemy fire.
Keep on going down, try to ram the Jackals if you can; however, if you can't don't worry, they don't harm you much unless you are trying to get yourself killed by standing in their way; proving you a very easy target.
Go down the waterfall, where you'll meet Brutes on the floor and Jackals on the bridge-like thing above. Kill them if you want to, but it's not compulsory and proves a waste of time.
Keep on going down the waterfall and then, down the jump, into the fray of enemies. Your allies might follow you from here, but it's unlikely, after all the skipping you have done.
Part 03: Fight Club
You may want to snipe a bit on top of the falls (take the Beam Rifles the Jackals had.) Beware; your other Elite allies (especially the Zealot) will jump down and start attacking the Loyalists. As you jump down, your Ghost/Spectre might flip over. If it does, it's most likely it'll flip a fair distance from you; so don't bother going back. If you are still on your Spectre/Ghost, kill them. If not, just use your weapons. Once all the enemies in this section are dead, go under the bridge and there will be two Wraiths. You have two options to deal with the Wraiths. Board one and hijack it and blast the other with the hijack wraith main turret, or board one, and chuck a grenade in. Board the other, and repeat as so.
Go back to the other section, and find a ramp up. It should be on the right from where you jumped down from the waterfall. Get off the Ghost and kill the Brutes with your Brute Shot or remaining Energy Sword. They're no threat; the only threat is the Plasma Grenades they might throw. Get out your Fuel Rod Cannon and head towards the door you see on the other side of the bridge. Walk into it, and then walk backwards without facing backwards. Shoot your Fuel Rod into the fray of Brutes, they will die. If not, mow them down with your remaining Energy Sword or Brute Shot. Walk into the room, there might be one or two Brutes there. Kill them with any method possible. Swap your dead Energy Sword/Brute Shot for a Covenant Carbine, and try to pick up some Fuel Rod ammo. Don't worry about the Rocket Launcher, it's not of much use unless you purposely try to waste your Fuel Rod Cannon. Switch to your Covenant Carbine and go out the door. Shoot the Sniper Jackals, and kill all Brutes. Continue on, and you will see a cave. The first and second wave of enemies contains a Brute on a Ghost, you might want to steal that from him, and ram all enemies over. Then, continue through the door, and you have finished. Also the weapon you have right now you will have in the last level.
Congratulations, you have completed Uprising!