Chapter Ten: Cerberus Headquarters
Before beginning this mission, make sure you have completed any and all side-missions you have remaining, and that you’ve gathered all the war assets you could. Once you start this mission, you will not be able to return to the Galaxy Map again.
After learning where the Illusive Man is holed up, Shepard and the Alliance organize an attack on Cerberus HQ to recover the catalyst. EDI is a necessary squadmate for this mission, so make sure you’ve also got someone with decent firepower at your side.
Objective: Gain access to the Central Lab
Shepard’s shuttle is able to sneak aboard Cerberus HQ, but not without alerting virtually the entire base. As soon as you exit the shuttle, you’re thrown into the action against Assault Troopers, Nemesis, and Centurion soldiers. After managing to take all of them out, you’ll have to contend with an Atlas mech. Once the mech is out of the picture, climb up the ladder on the left hand side of the hangar. Cerberus plans to vent the hangar, and you’ve got to activate the controls to stop it.
Once you reach the upper platform, EDI works on overriding the ventilation controls. Cerberus Guardians come from down the hall. After you take them out, you’ve got to get to another terminal on the other side of the hanger. Follow the upper catwalk around, eliminating the Cerberus forces you encounter along the way.
Drop back down to the hangar by using the ladder just outside the control room. Find the control panel to release the fighter jet to your right, and activate it. Once you send the Cerberus vehicle careening through the wall, two Atlas mechs and a handful of soldiers will show up. You can deal with them on foot, or you can hop in the newly unlocked Atlas mech on the right hand side of the hangar.
Approach the giant hole you created in the hangar wall. To the left you’ll find a M-37 Falcon. Pick it up, and then continue to the door in the left corner of the room. Hop down the ladder to the service tunnels. Be prepared to face off against Assault Troopers and Centurions as you make your way through the sub-level. The path will wind around until you come to another ladder. Climb up, and you’ll find youself in a lab. While EDI works on opening the next door, you have the opportunity to watch some old security footage that will shed some light on the Lazarus project.
After EDI gets the door open, proceed out into the hall, and turn around the burning crevice to the right. Drop down into the service area once again. Now there are Engineers along with Assault Troopers and Centurions. There are also some Shield Generators set up at key locations. Try to take them out before getting into a prolonged firefight with Cerberus. Carefully use flanking techniques to get past this area without too much resistance. Once you’ve taken all the Cerberus forces out and have found you way around, climb up the ladder into the next section of labs.
The console on the left has more security footage to check out, which will shed some light on EDI’s past. Make your way through the door, and into the next room. There’s a Medical Station on the left wall. When you head out into the next hallway, there will be an opening in the wall on the left with a blue light emanating from it. Don’t go down the hole immediately. Instead, proceed to the end of the hall, and into the next set of labs on the right. There you’ll get the Delumcore Overlay, and find yet another set of security videos if you are interested. After checking those videos out, head back to that blue hole, and jump in.
Make your way along the catwalks. Shepard and his squad realize Cerberus is holding the Proto-Reaper’s remains here. After the short cutscene plays, head up the ramp. Immediately Phantoms, Nemesis, and Assault Troopers will attack you. There are also some Shield Generators hidden behind cover. It’s tough to take them out without getting caught in the crossfire, so you’ll just have to hope you don’t run out of ammo before finishing off the opposing forces on the catwalk.
Once they’ve all been taken out, continue climbing the ladders and making your way across the catwalk until you reach a door.
Objective: Activate the Prothean VI
When you come into the next area, you’ll find a Med Kit and some ammo on the ground. Grab it, and then head through the next few sets of doors. This will bring you into the Illusive Man’s chamber. After a lengthy cutscene, Kai Leng arrives to finish off Shepard. The fight lasts three stages. After you whittle down Kai Leng’s shields, he’ll retreat to another part of the room to recharge, and sick increasingly difficult Cerberus forces on you.
Once you’ve finally managed to put an end to Kai Leng, Shepard can activate the Prothean VI. You learn the Citadel is the catalyst for the Crucible, but the Reapers have already seized it, and taken it into orbit above Earth.