Kirrahe and his men are attacking the base head on in hopes of diverting the attention of the geth. Though your primary mission is to infiltrate the base unseen, Kirrahe has asked you to keep an eye out for way to frustrate and slow the geth defenses.
Acquisition
This assignment is gained automatically during Kirrahe's comm check in, when he says any help undermining the geth would be appreciated.
Walkthrough
There are four distinct actions that assist Kirrahe's team. Helpfully, they are usually announced over radio chatter by Ashley or Kaidan (depending on who you sent along) or Kirrahe himself.
Note: These actions must be completed in the order they occur. Skipping certain actions and coming back to do them later will result in Kirrahe's death.
Disrupt Communications
While attacking the first geth station you come to, one of your squad will comment that the geth seemed very keen to protect that outpost. Find and activate a geth control panel on top of the platform to mess up their triangulation.
Destroy the Satellite Uplink
On top of the second station, just past the Geth Rocket Drones, is a satellite dish. One shot, Throw or Singularity will knock the dish off the roof and destroy it.
Destroy Flyers
Nearing the base, Williams or Alenko will mention over radio chatter that geth flyers have forced them to bunker down. Circle around the facility to the right to find the re-fuelling platform, and hit the fuel tanks first to destroy the flyers.
Disable alarms
When entering the base, either by the sewers or the warehouse entrance, there are consoles you must use to open the locked door nearby. You get two options — to either disable the alarms (thus more fighting for your squad) or trigger them at the far side of the base (sending them towards Kirrahe's team, but less enemies to fight for you).
Note: If you accomplished the previous objectives but triggered the alarms at the far side of the base, Kirrahe's team will be flanked but this does not result in the captain's death. If you're not in the mood to fight additional enemies, this is one objective you may skip and still have Kirrahe alive at the end.
By the time you are right outside the base, there will be some radio chatter. If you assisted Kirrahe's team, he will be on the radio mentioning that the Shadow team is coming through with help. If not, Williams or Alenko will be on the radio saying that they are taking heavy fire and that Captain Kirrahe is down, and will be on the radio for the remainder of the mission.
Once the mission is over, when Shepard goes to the lower levels of the Normandy next to Wrex, there will be a group of salarians. If Kirrahe survived, he will be there too and say that perhaps he will see Shepard again one day. If not, he will be absent from the group.
Mass Effect 2 Consequences
When talking to Mordin Solus about personal questions, he will mention that he worked under Captain Kirrahe in the salarian Special Tasks Group. Shepard will mention that they worked with him on Virmire to destroy Saren's cloning facility.
- If Kirrahe lives, Mordin will talk about him and mention his reference to his "Hold the Line" speech.
- If Kirrahe doesn't live, Mordin briefly eulogizes him.
Mass Effect 3 Consequences
If Kirrahe survived the events on Virmire, then when Shepard visits the salarian homeworld Sur'Kesh to rescue a fertile female krogan, the now-promoted Major Kirrahe will provide some assistance to Shepard and the squad. He can appear again on the Citadel, provided that Thane either died during Mass Effect 2, or was never spoken to on the Citadel. Kirrahe will save the salarian councilor's life from Kai Leng, but die in the process.
If Wrex survived Virmire but died years later due to Shepard sabotaging the genophage cure, Kirrahe and his STG unit will appear in London instead of Wrex and his krogan.