This mission starts after you grab Grunt. Feel free to free him if you want him for the next mission, but Garrus can do the same job.
Contact
Bit of running around you could do, but I think all you need to do is use the conference room to speak to the boss. You are then immediately sent to Horizon.
Overload is not needed, these enemies will have barriers. Just bring Mordin and Garrus.
Move up and fight the first group of Collectors; just fight through their barriers, biotics work well after that. Power cells in the middle, then a data pad, and head around the corner. Drop down and you can take refuge to the right inside the buildging. Watch for the melee enemies that charge at you. There is money in here and an upgrade to grab from a body on the ground.
Head up the hill and examine the body. Up ahead is a fight. Best to take the right building to flank them. There is gel in the left building and a hack in the right one. Take the steps along the way up to a room with a computer, then come back down and cross the field for a quick scene.
The burning one is the one to target, and you’ll need to take him out twice. Do so and take out the rest from a distance. Don’t miss the steps on the left, probably behind you, for a computer on the first floor, but nothing up the steps. Power cells in the corner building, and a beam gun on the left side of your way to the next door. Bypass for scene.
Ore and a chance to swap your heavy guns. This beam cannon is strong against all but flesh, so keep it. Head through the door and get ready for a pretty tough fight. Cut a path left and hide from the Scion husk that is walking around. Take out the harbinger and then the Scion, using your beam gun. Have your unity ready.
After the fight, go left for power cells, head right for an upgrade on a body, take the stairs up for a computer, and then realize this entire area was intended to be used for fighting the Scion – oh well. Bypass the door.
In the middle will be two Scions. And if you didn’t realize last time, they send out shockwaves. Dance to avoid these, focus beam fire on one (as well as powers), and avoid the smaller husks. I just used the cover near the door as I took out the Scions, it was the husks that kept bugging me, but I just avoided them as I killed each Scion.
After the fight, some cells to the left and right, then use the computer in the middle of this field.
Save your beam ammo. You got two waves of enemies, from the top and the left I believe, and there are two harbingers in with each. The second wave is tough because you need to dispatch the incoming husks.
Finally, a huge mech flies in and you need to get its armor to zero. The beam does this quite well, it’s just a matter of staying behind cover as it hovers around. The square blocks toward the entrance doors do this well, but you don’t want the thing directly above you, so you’ll have to move most likely. The barrier refreshes, so you need to waste its armor between barriers, and if you use two different guns on each that may help.
