Guide UNC: Depot Sigma-23 in Mass Effect: Legendary Edition (ME1)

Q: How to start UNC: Depot Sigma-23?

This assignment becomes available after finishing Noveria and completing UNC: Listening Post Alpha and UNC: Listening Post Theta. Head to the Unidentified Space Facility in the Gorgon system, clear out the Rachni, examine the terminal, set the demolition charges, and escape within 70 seconds before the facility explodes.

Q: Where is the Unidentified Space Facility?

This assignment becomes available after finishing Noveria and completing UNC: Listening Post Alpha and UNC: Listening Post Theta. Head to the Unidentified Space Facility in the Gorgon system, clear out the Rachni, examine the terminal, set the demolition charges, and escape within 70 seconds before the facility explodes.

Q: What happens at Depot Sigma-23?

This assignment becomes available after finishing Noveria and completing UNC: Listening Post Alpha and UNC: Listening Post Theta. Head to the Unidentified Space Facility in the Gorgon system, clear out the Rachni, examine the terminal, set the demolition charges, and escape within 70 seconds before the facility explodes.

Q: How to escape Depot Sigma-23 before detonation?

This assignment becomes available after finishing Noveria and completing UNC: Listening Post Alpha and UNC: Listening Post Theta. Head to the Unidentified Space Facility in the Gorgon system, clear out the Rachni, examine the terminal, set the demolition charges, and escape within 70 seconds before the facility explodes.

AntMag.NET

Walkthrough

1
How to Begin: To unlock this assignment, you first need to complete the main story events at Noveria’s Rift Station. After that, tackle both UNC: Listening Post Alpha and UNC: Listening Post Theta in any order. Completing Alpha first will give you the location of Depot Sigma-23 from a terminal in Theta. If you do Theta first, Lieutenant Durand will point you toward the depot. The assignment officially starts when you enter the facility.
2
Explore the Unidentified Space Facility: Travel to the Gorgon system within the Argos Rho cluster and dock with the Unidentified Space Facility. Once you disembark, proceed to the main room. You'll immediately be ambushed by a Rachni Soldier and several Rachni Workers. Don't rush out into the open; focus on the Soldier first, which appears to your left as you enter the room. Once the immediate threats are dealt with, take a moment to loot the main room.
3
Find the Terminal: Continue to the back of the facility. At the intersection, first head into the room on your right. You'll find a good number of lockers to decrypt here. After looting, exit that room and go into the one directly in front of you. (The room on the far right at this intersection contains nothing of value). Examine the terminal in this room and listen to the audio logs. These logs will explain the situation involving Cerberus and the Rachni, with the final log suggesting you detonate the charges.
4
Escape the Facility: Before interacting with the Demolition Charges, it's a good idea to make a manual save. Accessing the terminal will prime the charges, giving you exactly 01:10 (70 seconds) to reach the Normandy and escape the impending explosion. This escape is made more challenging by the fact that more Rachni will appear and try to stop you. Utilize your biotic abilities to disable them or simply gun them down quickly. You'll need to retrace your steps through the maze-like corridors to reach the airlock. Once you make it to the airlock, return to the Normandy to successfully complete the assignment.

Tips

The Rachni Soldier in the main room is the primary threat initially. Focus fire on it to quickly neutralize the immediate danger.
Don't forget to loot all the lockers in the side room before proceeding to the terminal.
Make a manual save before activating the demolition charges, as the timed escape can be tricky.
Use your squad's abilities, especially crowd control or disabling powers, to manage the Rachni that appear during your escape.

100% Human-Written. AI Fact-Checked. Community Verified. Learn how AntMag verifies content