Tip of the Spear
Run straight up the hill so that you can see both of the Grunts in the Shade Turrets, then DMR them out as quickly as you can. This will trigger the Pelican to make its way over to the road to drop the Warthog. While the Pelican is flying to the road, backsmack the Elite with the Concussion Rifle, as it is required for a skip at the mining facility later on. There are other options for skipping the mining facility which I'll explain later, but if you're experienced with concussion jumping, I recommend bringing along the Concussion Rifle. Get in the Warthog and make your way to the first AA Gun. When you can see the AA Gun, head towards it to the right, and you should pass a little slope with a tree at the top of it on the left. Drive up it, park your 'Hog next to the AA Gun, destroy the Gun by any means (I shoot the shield then toss a grenade into the core but anything works), then get back into your Warthog and drive it to the Ghost that lies upside down past the AA Gun. Take the Ghost up to where the bridge drops, wait for the bridge, then head for the mining facility. When you come into the clearing and can see the mining facility, save up some boost, then approach the wall of rock on the right of the mining facility. Drive your Ghost up and along the wall so that you end up on the other side of the bridge. Now get on top of the stack of metal sheets and stand facing away from the slanted roof, then concussion jump to the lowest point on the slanted roof. Continue through the rest of the mining facility. When you get to the ordinance you should have a Concussion Rifle from the Elite at the beginning and a DMR that you spawned with. Switch the Plasma Launcher for the Concussion Rifle. Hop into the Revenant and continue towards the second AA Gun. When you see the Warthog on the bridge, head down the road to your right until you see the AA Gun on your left. Save up some boost and boost your way up the slope to the AA Gun with your Revenant. Hop out and run inside the Gun. You'll see a pair of Hunters. Shoot a few Grenades at them with the Plasma Launcher to weaken them for later. If you haven’t thrown any Nades since the first AA Gun, you should have a Plasma Nade. Throw it into the core before the shield generates, but after you shoot the Hunters. Head back to your Revenant and take out the enemies as quickly as you can. I recommend shooting groups of enemies and splattering. Watch out for the Wraith though, as somehow - even on Easy - it can kill you by splattering you IN YOUR REVENANT. Tweet how you're on WR pace in Halo Reach while you're in the Falcon. After the cutscene, run to the left, grab the Health Pack and a Plasma Pistol, but only if a Grunt spawns in your path. You'll be running towards the truck on the left side of the map, so some of the Grunt spawns aren't worth the time loss to go pick up their gun. Drive the truck the base of the Spire and take the elevator. Try to nade most of the Grunts and backsmack the sword Elite before he finishes drawing his sword. Activate the button and you're done.