Mahavid: Leviathan

Alex Garneau is missing on Mahavid, which is under Reaper attack. Find Garneau and learn more about Leviathan.

Acquisition
Complete Leviathan: Find Garneau.

Walkthrough
You'll be facing Reaper enemies on this mission, so choose your team with this in mind.

On the way down to the asteroid in the shuttle, Shepard, Cortez, and your squad will discuss the mission and the evidence you've found while you were searching Dr. Bryson's lab. After the short mission briefing, Shepard and the squad will land on the asteroid mining facility.

After exiting the shuttle, take the nearby lift down to the main floor. While moving off the lift, your squad will notice a small Reaper scouting party ahead, near the door to the inside of the facility. The Reapers here consist of about two Marauders and a Brute. Once you finish off the two Marauders and the first Brute, a second Brute will come down the stairs near where the Reaper party was spotted. There's plenty of cover nearby, and if you act quickly you should be able to take them out easily. There is an ammo pile on the right wall.

Head up the stairs where the Reaper enemies were located to find a Med Kit and a second ammo pile, if needed. Bypass the only accessible door to the left, and head on through to the next room. Here you'll find yourself in a reception room with T-GES Mineral Works employees hanging out, oblivious to the Reaper party that you and your team just cleaned out. Shepard and team will talk to the personnel at the reception desk, and after asking about Dr. Garneau, you'll find that the elevator is inoperable. You'll have to find a way to repair it so you can move on.

After regaining control of Shepard, you'll be able to look around, eavesdrop on some of the other personnel talking with each other, and find that you now have to repair the elevator. There is a datapad near the group in front of the customs personnel you can interact with to get some more information and 1250 credits. There is another datapad behind the reception desk that also yields credits, 2500. The men behind the reception desk will make threats while you're behind the desk, but they are not hostile.

At the far side of the room away from the door you took to get into this room, you'll find a Repair Drone Terminal you can use to activate a drone to fix the elevator. Stay near it to guide it to the elevator (this section is familiar for players who play multiplayer). After fixing the elevator, take it up to the next floor.

Inside this hallway, you can find a datapad behind a crate of rocks to the left worth some experience, or 1250 credits. Then move through either door, as both lead to different parts of connected rooms. There are various objects you can interact with that show that T-GES Mineral Works is not what it seems. The door to personnel quarters is locked for now but that will be dealt with later.

Check out the security terminal with the floor map: you need a password for further clearance. Now head to the next room with more creepy workers; behind the 3D display console, there's a door to bypass. Inside the room is an SMG High-Velocity Barrel and a datapad with an undelivered message by Dr. Garneau to Dr. Bryson - which contains a working password.

But before you return to the security terminal, head towards the medical bay. It's locked for now but the objective is the security station next to it - a datapad with a working personnel ID can be found there.

Now head all the way back to the personnel quarters, with a valid personnel ID you can now enter. There is an Ultralight Pistol Materials mod and two datapads with information date-stamped almost ten years before.

Return to the security terminal and access it. It will play a security footage of Dr. Garneau's arrival to this facility earlier; but more importantly it gives you a patient number for accessing the medical bay.

Once inside, there's a medkit available for pickup next to a windowed room with a corpse in a table. Interact with the window to meet Dr. Garneau. After a conversation it turns out this person is being controlled by the Leviathan and it makes the thrall run away. Give chase but after the second door the only way is through the access ladder going outside.

Once out, follow the linear path towards the objective, and you'll soon notice that the Husks are doing something rare - instead of rushing towards you as usual, they chase after Dr. Garneau. Deal with the stragglers in your way and move on to the next clearing. Grab the SMG Mass Pulse Recoil System mod along the way.

Now this is the main battleground for the remainder of the mission, terrain-wise there's cover everywhere to use and the closest elevation has a Reaper Blackstar for special occasions. It's better to leave the Blackstar there for now, bear with using conventional weapons first. The objective is at the far end but this time, the Reapers are determined to stop you. Marauders, Ravagers and conventional Husks will spawn to block you. A pair of Banshees will join in the fight after you've dealt with the initial wave. But if you think you're good at ducking while under fire, you can simply rush to the other side and you can preempt the appearance of further enemies.

Whatever you choose, there's still a Ravager and a couple of Husks guarding the door that needs to be dealt with, if they haven't joined the battle at the open area. Once they're dead inspect the area just next the door and in front of it for a medkit and a Pistol Cranial Trauma System.

As you access the door, power goes offline and now you have to escort a vulnerable repair drone to repair two power units, located in the two separate elevated positions from the you just came through. Stay close to the drone to guide it, but here comes the second half of the fight - Marauders and Ravagers will crash the party. Once the first repair is complete it's time to escort it to the second unit. Choose your path wisely, the drone is slow to navigate obstacles. As you get close to the second power unit you'll hear the Banshee scream - the good news is that it's the last enemy on this level, the bad news is they came from behind. If you're low on ammo or have yet to use the Blackstar, it's as good time as any to unleash it. Once repair is complete you're clear to proceed.

Open the door and into the mine, you'll see Dr. Garneau is back towards the artifact and surrounded by Husks. Instead of giving you a clear shot at the Husks, he detonates the artifact, killing him along with the rest of the Husks.

Examining the area your squadmate will discover the real Dr. Garneau's body. It turns out the man you were chasing was an impostor after all. Some of the facility's personnel, apparently themselves again, approach. Not only have they no recollection of who Dr. Garneau is, they actually have no recollection of anything other then being somewhere dark and cold. When Shepard questions them about Reapers attacking the base, they don't know what is a "Reaper"; finally, Shepard asks them what year is this. One says 2176 - apparently the Leviathan has held the facility's personnel as thralls for ten years.