Delta Halo Walkthrough
From Halopedia, the Halo wiki
Part 01: Helljumpers
As you land, move to the ramp. Use a locked rocket to destroy the nearest Shade, then take cover from the Grunts and pick them off with your SMG. Go through the archway and up to the top. Destroy the Shade in the building on the far side, and if you're lucky, you will kill the Jackal Sniper as well. If you don't kill it, grab a Battle Rifle from the drop pod nearest to you (swap for your SMG) and shoot it in the head. Stay out of its sight until you are ready to kill it or you will die. Proceed to the structure where the Jackal was, destroy any remaining Shades, then swap your Rocket Launcher for a Plasma Pistol. Use the resulting Noob Combo to kill the Elites and the Battle Rifle to kill the remaining Grunts, but stay in the structure.
When the courtyard is clear, grab a fresh Plasma Pistol and return to the structure. Grab some Battle Rifle ammo from the nearest drop pod. Stay out of view of the Phantom, then kill as many enemies as possible as they drop. Kill the remaining enemies with the Noob Combo. There are 3 Grunts, 3 Jackals, and 2 Elites.
If the next Phantom doesn't show up, it is because you have not destroyed the first wave. Enemies often camp on the first floor, so drop down to the ground, reenter the structure, and kill them from behind. Alternatively, pick them off from the ramp, using it as a choke.
When the Phantom does show up, it will drop 5 Grunts, 2 Jackals, and 2 Elites, which may be Ultras. If they are Ultras, try to provoke at least one into drawing his sword, then kill him. Otherwise, one will already be holding a sword.
The last Phantom will drop three Stealth Elites. If you're quick, you can snipe them before they engage camouflage—they will die to a single headshot if you do. If any survive, kill them with the Noob Combo.
When the Warthog drops, grab the rockets above, then hand a Marine your Rocket Launcher. Grab a Beam Rifle (there should be one with 18 shots behind the destroyed base of the Shade) in exchange for your Plasma Pistol, then get in the Warthog. If you provoked one of the Ultra Elites to the point that he drew his sword, take it. Try to get your Marine with the rockets to ride in the passenger seat.
Drive down and let the Marine on the turret kill the Jackal Snipers. They are not instant-kill because you are in a Warthog. Drive to the hill overlooking the bridge, but don't trigger the Wraiths yet. Get out and snipe any Elites. Let your Marine's infinite rockets kill any Ghosts and Shades in this area. Drive around the right and approach the bridge-control building from behind. Get out of the Warthog and enter the structure.
There are three enemies in the center—a Grunt, a Jackal, and an Elite. Kill them by tossing a few fragmentation grenades and hopefully sticking the Major Elite, then lower the bridge and prepare to use heavy armor. Be careful to hurry once you lower the bridge, however; the Wraith can now hit you without the obstacle.
Drive the tank through, destroying anything in your path. After you go back outside for the first time, destroy the two Plasma Cannons. Keep going until you reach the next courtyard.
Part 02: You Break It, You Buy It
As you enter the next area, destroy all of the Shades, Ghosts, and infantry. If you don't have a sword, grab one from the dark room near the Envy Skull, unless you don't want to use all of your grenades. Keep it for the rest of the level.
Get back in your 808 and go under the structure and kill any visible Covenant. Get out and pick off the rest. But be careful—if you don't kill the Elite quickly, he will get in your tank and kill you with the 90mm cannon.
Kill the Covenant behind the shields, then swap your nearly empty Beam Rifle for a Sniper Rifle.
Kill the Covenant in the center, with Marine support, and kill the Elites on the top with a few grenades.
Kill the Grunts and Jackals in the next clearing. Your sword should be depleted, but keep it.
Part 03: Off the Rock, Through the Bush, Nothing but Jackal
Assassinate the Jackal Sniper ahead of you, then steady your aim, because you are about to enter a frenzy of sniping and no scoping. Take the Beam Rifle from the Jackal you just killed, making sure that your Sniper Rifle falls down the waterfall. Snipe the Jackal to the right and below you, then drop down. Snipe the Jackal across the valley, then walk toward the waterfall.
When you hear Yanme'e, take cover in the small cave and look upstream. Use your scope to hit the Drones as they fly into your view (one shot anywhere should suffice), but keep an eye on your motion tracker and be ready to turn around and take out anything behind you.
After the Drones have been killed, carefully step out and snipe any Jackals you see. Kill the Elite Major with a shot anywhere, then to the head. Your Beam Rifle should be about empty; grab a fresh one from a small alcove behind the waterfall. Climb up the ramp, then immediately back into the small cave in the valley because there are more Drones.
Kill them, then go back to the ramp and enter the larger cave. There is an Elite—snipe him, then go up the left side. More Drones will show up, so enter the cave with the ODST and no scope them as they fly into view of the mouth of the cave. This time, the no scoping should be relatively easy. Go back and kill the Elite and the Jackal.
Grab a fresh Beam Rifle, then continue to the view of the temple. But don't drop down—first, take out the two Jackal Snipers, then snipe the Drones. Go back for the other Beam Rifle. Enter the temple and prepare to face your first Honor Guards.
Kill three of them, then go back to the valley and grab a Sniper Rifle. Stick the last Honor Guard, then back off and the level will end. If you held onto your depleted sword, it will become an Infinite Sword, which will be extremely helpful on the next level.