Priority: The Citadel II

The Salarian Council member contacts Shepard with concerns about large sums of money moving through the bank accounts of Council member Donnel Udina. He asks that Shepard comes to the Citadel so they can get to the bottom of it.

Acquisition
Acquired once Priority: Tuchanka has been completed.

Note that Priority: Tuchanka is the "point of no return" for several side missions (listed on that mission's page), which must be completed before The Shroud. Likewise, two missions expire once you begin this one:
 * Grissom Academy: Emergency Evacuation (this one may have expired of its own accord by now)
 * Tuchanka: Bomb

Walkthrough
The mission begins when the Normandy approaches the Citadel but is not cleared for landing. Joker contacts someone inside the Citadel &mdash; Thane Krios, if he's alive and if you spoke to him during Priority: The Citadel I, or Armando-Owen Bailey if otherwise &mdash; who explains the situation: Cerberus has attacked and partially taken over the station, particularly C-Sec Headquarters. Shepard deploys with a team to clear them out. Warp Ammo, Disruptor Ammo, biotics and Sniper Rifles are recommended, particularly with the Concentration Mod equipped.

C-Sec HQ
Shepard lands outside C-Sec HQ, and must fight uphill against Cerberus troops supported by Shield Pylons at the far wall. The central path is the most direct and a good place to exercise your sniping skill, but side paths branch off as well for easy flanking or access to the Shield Pylons. Left of the locked door is a Med Station that can be salvaged. Once the enemies are fought off, Shepard finds Bailey wounded near the door. Bailey lets them inside C-Sec HQ, where he discovers that the salarian councilor (either Councilor Valern or Councilor Esheel) has taken refuge in the executor's office, where (Bailey hypothesizes) she was preparing to make accusations against Donnel Udina. Bailey directs Shepard's party to that location; if Thane is present, Shepard vectors him in as well.

Up the stairs of the next room is a medkit and an Assault Rifle Piercing Mod, but acquisitive players should be aware that troops will jump down from the second floor. Afterwards comes a small room with active fire sprinklers, and then a room where at least one Guardian and his riot shield faces the other direction, a prime target for ambushing. Beware of the Centurions though, of a Combat Engineer on the high ground to the right, and of the fact that the room is basically three parallel hallways: while you're focusing on said Guardian and Combat Engineer, Cerberus can flank you from the left. Once clear, loot the room: there's a Recon Hood on the left, a medigel station against the far wall, and a door on the left side that leads to a bathroom containing credits, an M-76 Revenant and the loot's hapless former owners.

In the next room you'll find broken windows, on the other side of which is another Combat Engineer helpfully looking the other way as he fiddles with the elevator. With him are a weapon bench, a Sniper Rifle Extended Barrel, ammo pickups and another latchbox protecting the elevator controls. The elevator takes you to a room with more corpses and more loot: a Pistol Piercing Mod and Bailey's Personal Log on the right, the M-25 Hornet down the middle right before the malfunctioning door, and on the left a Securitel helmet and Pistol High-Caliber Barrel Mod, as well as a locked door. To open this door, go to the right side up near the malfunctioning door and use the Door Control terminal in the side room. Then go diagonally back and help yourself to a datapad describing the actions of a weapons smuggler, as well as an example of said weapon, the M-358 Talon. Finally, go back to where you found the Door Control to exit this area.

On the other side of the door you'll find two more preoccupied Cerberus soldiers, this time executing a C-Sec defector. After that you'll enter a cafe area, with the kitchen on your right. This is one of the better places to hole up, because a number of Cerberus soldiers will flood in and you have to fight them off. Just beware that there's a set of stairs leading downward in the middle of the room, and to clear the enemy from it you'll need to physically go there. It might also be wise to post one of your teammates in the hallway next to the kitchen, so that Cerberus can't flank you from there. Two medstations, one inside the kitchen and one on the far wall, are available if you need the help. There's also some credits against the back wall of the kitchen, a Sniper Rifle Piercing mod near the far wall (you'll likely see it during the firefight), and--for a bit of flavor--a flatscreen TV in the corner of the cafe broadcasting a news report. It's Khalisah al-Jilani, covering C-Sec's attempts to reclaim the Citadel's comm towers so that they can send a distress call. She is doing her part by including a direct plea for reinforcements in her broadcast coverage, which has been piped throughout the station. (For once, no snide insinuations are in evidence.)

Up the stairs against the back wall, you'll find the executor's office. He's dead, but the salarian councilor is nowhere in sight. Your squad members will find him/her under cloak down in the cafe area you just left, but before you can get down there, Kai Leng will arrive to ruin your party. The salarian councilor gets out the critical information that Udina is planning a coup before one of several things happen:
 * If Thane is around, he will intervene, allowing you to save the salarian councilor but getting stabbed in the process.
 * If Thane is not around but Captain Kirrahe survived the events of Virmire, he will intervene, allowing you to save the salarian councilor but getting stabbed in the process.
 * If neither character is around to intervene, Leng will be able to kill the salarian councilor.

Whatever the case, Shepard calls Bailey, and Bailey unlocks a C-Sec police car for Shepard's pursuit. Using transponders, Bailey determines that Udina is leading the Council to a landing pad near Shalmar Plaza, where Kai Leng is presumably waiting for them. In his spare time, though, Leng decides to interfere with Shepard by attacking the police car with his sword, seriously damaging it and putting Shepard's party on foot in the Commons.

Presidium Commons
This next fight is the introduction of Cerberus Phantoms, who have biotic barriers, are extremely agile and have a melee-range one-hit-kill; and Nemeses, who are barrier-shielded and have a sniper-rifle attack that will knock off all your shields. Keeping your distance, or using disables on them like Concussive Shot, Carnage or biotics, is your best bet against them.

The first area has a stairway that will allow you to circle around the Cerberus lines and attack them from behind, but this is not necessarily advantageous: both Phantoms and Nemeses are slippery, Phantoms are most dangerous at close range, and your teammates can probably take them out before you get round. Next you'll have to running-jump to a new section, where all manner of opposition awaits you: Phantoms, Nemeses, and--worst of all--no room to maneuver. One good bet is actually to jump back across the gap, which will funnel the enemy into a choke point that Singularity will easily block up. Alternatively, grab your shotgun, keep moving, and have eyes on the back of your head.

Head down the parking garage towards the door, which Cerberus will seal behind them. Jump the wall to your right and then keep heading up towards Shalmar Plaza using the "back alleys." You'll find a datapad with credits on the way; to continue from that point on, put that pad behind you and you'll see the next alleyway. The next zone has an Atlas Mech if you care for some hijacking, but don't take it easy if you've gotten it, there's still more baddies in the area. Finally, take the stairs for a trip atop an elevator.

The final combat zone of the mission can be easy because enemy reinforcements approach via elevator cars, all of which have Power Conduits on the top and bottom that you can shoot out, halting the lift car's progress entirely. However, this zone can also be challenging because the cars come from both sides, and contain Phantoms. And there's basically no room to maneuver. If you remain on top of things, sniping out cars as soon as they arrive, you ought to be fine, but one mess-up could be a game over. If so, take a deep breath and try again. There may not be much margin for error, but the tasks themselves are not actually difficult. A sniper rifle with Concentration equipped might be your best friend, due to the time dilation; obviously, having Adrenaline Rush is just as useful, if less accessible. But the easiest way is to use Overload on the conduits, which can't fail if aimed properly. If you and another squad member both have it, you can get through this sequence without firing a shot.

Final Confrontation
Finally, a car will arrive that you have to jump on instead of shooting. It has the councilors in it, as well as the Virmire survivor (Ashley or Kaidan), who detects your landing and immediately fires at you through the roof. A short cutscene plays, and the Council's newest Spectre stands between you and the Council.

Choose either the Paragon or Renegade interrupt to talk down Kaidan or Ashley. If the salarian councilor is alive, they will listen and stand down. Shepard explains that Udina is behind the coup, but Udina dismisses the claim. When the asari councilor tries to stop Udina from unlocking the door that prevents Cerberus troops coming through, Udina pushes her down and aims a gun at her. Either Kaidan or Ashley, or you through a Renegade interrupt, will kill him.

Alternatively, if you didn't pick the interrupt and the salarian councilor was killed earlier, Udina will attempt to frame Shepard for it, making it much harder to convince them that Udina is lying. Without a sufficiently high Reputation, Shepard is forced to kill the Virmire survivor. Unfortunately, a squadmate will take the shot if you can't find it in yourself to do so. Afterwards, Udina gives up and pulls a gun. At this point, another Renegade interrupt lets you kill him. If you did not interrupt and if Kaidan or Ashley is still around, they will take the shot. If they aren't, Shepard will take the shot instead and comfort Kaidan or Ashley in their final moments.

Aftermath
Kai Leng reports the failure to the Illusive Man, confirming (in case you needed it) his connection to Cerberus, and Bailey follows up on C-Sec's inability to catch up with him. Other results include:
 * If Thane was present, Bailey will mention that he has been taken to Huerta Memorial. You may choose to be with him in his final moments. If Thane: Sins of the Father was completed, Kolyat Krios will be present as well. Kirrahe does not benefit from a similar cutscene, as he expires from his wounds on the spot.
 * A new set of side missions and Citadel missions will crop up, as well as Priority: Geth Dreadnought. See the Mass Effect 3 Guide for details.
 * Assuming you didn't shoot Ashley/Kaidan, they will be waiting for you at Normandy Dock: Bay D24. You may ask them to rejoin your squad or order them to remain on the Citadel, where they will become a War Asset (25). Once you get aboard the Normandy and vid-comm with Hackett, he'll mention the asari's recent commitment of War Assets as well, such as the Asari Science Team (90), Asari Second Fleet (90) and Asari Sixth Fleet (90). Finally, if you sided with the krogan at the Shroud, salarian forces will commit to you as well, in thanks for your rescue of their councilor. It can either be the STG Task Force (70) or the Salarian Third Fleet (125), depending on whether you rescued Valern or Esheel. (If you did not save the counciler from Kai Leng,and cured the Genophage you will not recieve Salarian War Assets for the final push.)