Didact's Hand/Random Transport/Walkthrough
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This Op picks up directly after your last one. Having leaped through the portal activated by the Covenant at Twin Giants, you hurtle out the other end, the facility known as Fortress...and directly into a large group of Covenant. First things first; FIND COVER.
This is easy enough to do; the portal drops you on top of one of the smaller structures surrounding the main one at Fortress's center. Inside, you'll also find exactly what you need to deal with the small army of Covenant outside; a UNSC weapons cache.
In addition to the standard small arms you expect, there's also plenty of juicy ordnance lying around. Grab whatever suits your fancy, but BE SURE to snag the two rocket launchers in the crates. They will come in HANDY in a short while.
Once you are geared up, move out and kill everything around you. By this point you should be quite versed in how to slaughter Covenant, so I won't go into the details of that. Simply kill. And then kill more. And then, when you're done killing, move on.
As you are killing, you will hear slightly garbled conversations between Miller, Palmer, and Roland. Most of them aren't particularly important to your current mission, but one is; Roland locates a still-working UNSC communications relay in the area. Your new objective; get that online so that Palmer and Miller can further direct you in your hunt for Jul 'Mdama.
Head towards the waypoint on your HUD. As you do, more Covenant will appear. In this case, they'll burst out of another of the smaller facilities...and amongst their number is a Hunter.
Kill the smaller infantry first, then use your Rocket Launcher to obliterate the Hunter. Once you have done so, go into the structure and retrieve the ammunition from within. With that out of the way, move to the waypoint. As always, there's more Covenant to kill. Do so, and power up the relay.
With the signal cleared, Palmer sends down new orders; power up the portals in the area and figure out which one Jul went through. Simple enough; go to the waypoint, killing anything in your way (be ready for more ambushes, including the second Hunter!) and power it up. Then, move to each of the two new waypoints that power up. Hit each one (which will spawn a new wave of enemies) and then fight your way up to the top of the middle structure. After a last, massive assault, you will be able to power up the portal and jump through, ending the mission.