A krogan team has gone missing, and Normandy has received the NavPoint with their last-known coordinates. Investigate the missing team and find out what happened.
Alternative journal entry:
A krogan scouting team has gone missing while investigating rumors of activity at the rachni relay. Investigate the missing team and find out what happened.
The mission is acquired automatically after completing Priority: Sur'Kesh. The journal entry is alternatively named as Attican Traverse: The Rachni, depending on your decision regarding the Rachni Queen in the original Mass Effect.
After you rescued the krogan female Eve, Urdnot Wrex, or Urdnot Wreav asks a "big favor" of you. A krogan scouting team has gone missing while investigating rumors of activity at the rachni relay. He asks you to investigate.
This mission makes frequent use of the M-451 Firestorm heavy weapon against both enemies and pieces of level geometry. If it is available, consider bringing the Particle Rifle along instead; it does comparable damage, is easier to aim and has much longer range. Also, consider equipping Dark Channel as your bonus power or bringing Javik in your squad: the level is filled with little scuttling enemies called Swarmers, and a single Dark Channel aimed at the front of a herd will wipe them all out.
Meet up with the Krogan team
Travel to the planet Utukku (Mulla Xul, Ninmah Cluster). Upon investigation you will meet up with Aralakh Company, led either by Grunt or (if he did not survive Mass Effect 2, or was never released from his tank in the first place) Urdnot Dagg. At mission start, check the krogan temporary barracks structure on your left for the M-300 Claymore shotgun, a Pistol High Caliber Barrel upgrade, and spare parts that you can salvage (+1625 credits). Further down the slope you come to a cluster of krogan structures, enter the leftmost building with the weapon bench to find a SMG High Caliber Barrel upgrade, as well as spare parts for salvage (+875 credits) outside the same structure, near two krogan soldiers. You can talk to Grunt/Dagg before entering the other building on the right. Once inside far enough, the building will fall down to the level of the tunnels and you will not be able to get back up to the krogan squad. You can only proceed forward, where you will find the body of a krogan scout and your first Firestorm.
Explore the tunnelsShotgun Shredder Mod along the left-hand wall. Proceed across the room, along the right is another scout next to some ammo, and in the center is a scout next to a Firestorm.
At the top of the ramp are a lot of spore pods. You will pass a blocked door on your left, and past more webbing will be a reaper node that you can destroy (+400 xp) to open the door. Take out the webbing past the door and the ceiling collapses trapping you on the far side.
Find the krogan team
Proceed forward, either up or down, it will take you to the same place. Then take out the webbing on the left so you can salvage some reaper tech (+3750 credits).
Continue forward and a husk will charge toward you. Take out the webbing on the left to find a dead krogan scout that will make Citadel: Krogan Dying Message available, though it will not appear in your Journal. You need to deliver his message to Ereba who is located in the Presidium Commons, behind the counter of Nos Astra Sporting goods. The second webbing on the right will have another scout behind it with a replacement Firestorm. Drop down into the large area ahead.Shotgun Spare Thermal Clip. Drop down over the ledge. Take out the gestation pods, and your squad should take out the swarmers inside. After taking out the pods on the left, salvage the reaper tech (+3125 credits). Keep moving forward, taking out pods. You will find another Firestorm next to a dead krogan. Jump across the chasm, take out some more pods, and further up the hill, next to another dead scout you will find Ariake Technologies Shoulder Guard right after a conversation about how the Reapers are breeding an army of rachni down here.
Climb up a series of ledges taking out the gestation pods as you go. Jump across a second gap and head down the hill to where you will see Aralakh company holding off reaper forces. Take out the gestation pods and the webbing and then destroy the reaper node. Grunt/Dagg will come through and tell you that the rachni have backed off, but will be coming back. He will defend this position so that you can "finish this." Make sure to pick up the med-kit and the Pistol Piercing Mod before leaving the room. You can also swap out your Firestorm.
Find the central chamber
Reaper fortifications will then extend upward out of the ground and encase you on the walkway. To bypass the walls, you must disable a Reaper node up and to the left of the forward fortification.
The left wall will retract once disabled, so be prepared to fight the waiting Reaper forces. Once they have been defeated, proceed toward their position and disable a second Reaper node, retracting the barriers on the right side of the walkway. Double back and exterminate the two groups of Reaper forces before disabling the third and final Reaper node. Fight against one last wave of Reaper forces; once they have been defeated, a cutscene will commence.
If you saved the rachni queen in Mass Effect, you will speak to her during this cutscene. If not, you will converse with the Breeder, a different rachni individual who was revived by the Reapers and has become indoctrinated. Either way, you may choose to either leave her or help her to survive. (Note that your decision will not affect the Reapers' supply of Ravagers one way or another.)
- If you leave the rachni to die, you will gain Aralakh Company as a war asset worth 75 points, but no rachni assets due to their xenocide and/or enslavement by the Reapers.
- If you choose to rescue the original queen from Noveria, Aralakh Company will suffer grievous losses in the holding action, reducing their strength by 25 points. However, the queen provides rachni workers worth 100 points to Project Crucible.
- If you choose to rescue the new Breeder, you gain a 50-point Aralakh Company and 100 points of rachni workers; however, the Breeder proves untrustworthy after a few missions, taking away her war asset and removing 100 points from the Alliance Engineering Corps.
No matter what you chose with the rachni queen, Grunt or Urdnot Dagg will stay behind to hold off Ravagers while Shepard's party runs for the shuttle. It is possible for Grunt to survive this if you completed his loyalty mission in the previous game. (If you did not, Grunt will mention his outsider status in his dialogue outside the falling prefab.)