1 - Surface Tension

Your arrival on Ilos is just moments too late. Saren has entered an underground facility in search of the Conduit, locking the doors behind him. Before you can proceed in the Mako you must navigate the planet's surface on foot to find a way to open the doors.

New Mission: "Ilos: Find the Conduit"

2 - The Ruins

Due south in the ruins are a pair of geth armatures. If you prefer to face them directly, be ready for a tough fight. Take out all the nearby soldiers so you can concentrate exclusively on the armatures. A combination of tech and biotic powers work well here. If you can temporarily disable one armature using Lift or Stasis then you can concentrate on fighting the other one using your tech powers. Alternatively, you can head west from the insertion point to reach a different part of the ruins. Though this area is more heavily guarded, it also contains an armature control console that can be used to deactivate the armatures so you won't have to fight them at all. Proceed south to the next area where more geth are waiting for you. Take the nearby elevator when all the geth are eliminated.

3 - The Security Level

The elevator takes you to a large room. As soon as you enter, a contingent of geth will rush in from the opposite side. Fortunately, you aren't alone in this fight: On either side of the room are a pair of armature repair stations. With sufficient decryption skill you can activate each of these stations to summon an armature to fight on your side against the rest of the geth. There is also a walkway near the entrance that you can use for some cover and a high vantage point.

4 - Prothean Security

Head to the back of the room and up the ramps to either side. These paths lead to a security panel you can use to open the doors and pursue Saren. A message appears but it is unintelligible. Head back down and take the north path to reach the elevator. This takes you back up to the surface where you can now enter the Mako and proceed through the open passageway.

5 - Constant Vigil

Following the straight path leads you to an energy barrier. When you get close enough, another barrier appears behind you. Your squad speculates that this might be a trap from Saren. Exit the Mako and take the nearby elevator. At the bottom is a VI interface known as Vigil, who explains that Ilos was the last refuge of the Protheans. Here they placed themselves in stasis and hid from the Reapers until it was safe to reemerge. However--after centuries of waiting--there were too few survivors left to sustain their population. They spent their remaining years trying to find a way to defeat the Reapers should they ever return. Because of the Protheans' efforts 50,000 years ago, the Reapers have been unable to return to the galaxy. However, if Saren succeeds, Sovereign will be able to summon the other Reapers from dark space and continue the cycle of extinction. The key to the Reaper invasion plan is the Citadel, which is actually an enormous mass relay connecting to dark space--the empty void beyond the rim of the galaxy. Sovereign needs to activate the Citadel relay, but would be unable to attack the Citadel directly because it is too well defended. Vigil explains that the Conduit is a backdoor onto the Citadel, which will allow Saren and his geth to penetrate the station's otherwise impregnable defenses and give Sovereign the control it needs to activate the relay.

+2 Paragon - "That's monstrous!" / "You betrayed them."
+2 Renegade - "It was necessary."
Mission Complete: "Ilos: Find the Conduit"
"Race Against Time: Sovereign" -> "Race Against Time: Conduit"

6 - The Conduit

Vigil gives you a copy of a special data file that must be uploaded into the Citadel's master control system to give you control of the station. This is your only chance to stop Saren and prevent the return of the Reapers. Head back up to the Mako and hurry after Saren. You need to navigate the trenches to reach the Conduit, though the path ahead is crawling with geth. Since you are in the Mako, your primary concern is the large number of rocket troopers you will encounter. At the end of the trenches you can see the Conduit, which is just a small mass relay. There is a limited time to reach the Conduit before the gate closes, so waste no time fighting the nearby enemies. Head straight towards the gate to be sure you arrive before time runs out.
The Mako is captured by the relay and propelled across the galaxy to the Citadel...

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FINAL NOTE

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I recommend that you try to finish the rest of the game on your own. There is not long to go, and I don't want to ruin the ending for you. If you really need help however, the rest of the walkthrough can be found in the Secrets section. Good luck and congratulations on making it this far!

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