Pick up the SMG before activating the security console.

M-4 Shuriken: Acquired during the Priority: Mars mission, found inside a lobby security room where Liara works at a computer.

M-11 Wraith: Can be purchased from Spectre Requisitions, from your Spectre Office in the Citadels, for 250,000 credits.

Geth Plasma Shotgun: Acquired during the Priority: Rannoch mission, entering a large combat area with the Geth stuck on a balcony, fight off the enemies and search right of the areas entrance to find this shotgun.

Disciple: Acquired during the Lesuss: Ardat-Yakshi Monastery mission, found after discovering the lone Asari, and entering a combat room filled with Cannibals and a shield generator.

Graal Spike Thrower: Acquired during the Priority: Tuchanka mission, found near a guard waiting by the railing just as the mission begins.

M-300 Claymore: Acquired during the Attican Traverse: Krogan Team mission, found in the abandoned camp in the left building just as you enter.

M-22 Eviscerator: Acquired during the Grissom Academy: Investigation mission, find this shotgun on a red couch after saving the first student.

M-27 Scimitar: Acquired during the Priority: Palaven mission, find this one in the main Turian camp on the ground as you exit for your first objective.

M-23 Katana: Given during the Priority: Mars mission as a starting weapon.

M-77 Paladin: This weapon can be purchased from Spectre Requisitions, a store console in the Spectre Office in the Citadel, for 200,000 credits.

Arc Pistol: Acquired during the Priority: Geth Dreadnought mission, where its given to Shepard by Tali.

Find this pistol on a pipe in the red-bathed maintenance hallway before taking the ladder up.

M-6 Carnifex: Acquired during the Arrae: Ex-Cerberus Scientists side-mission.

Run back, open the door, and claim your pistol among some other weapons. Continue ahead down the only path forward, and youll find a computer console that will open the office door.

M-358 Talon: Acquired in the mission Priority: The Citadel, while in C-Sec HQ, youll enter a dark hallway with four offices.

M-5 Phalanx: Acquired in the mission Priority: Tuchanka, find it on the ground, up the steps leading to the long stretch where the Reaper begins firing its laser at your team.

After reactivating the power, find the weapon before turning on the elevator.

Scorpion: Acquired in the mission Priority: SurKesh, find the weapon on the floor where Mordin requires you to reactivate the elevator power source.

M3 Predator: First weapon acquired during the Prologue.

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