How to Get the "No One Left Behind" Achievement in Mass Effect 2

Mission Probability: 0% // Threat Level: Terminal // Clearance: Shepard

The "Suicide Mission" in Mass Effect 2 is not hyperbole. It is a tactical simulation where command decisions have immediate, lethal consequences.

Unlike other RPGs where "friendship power" saves the day, the Omega 4 Relay respects only preparation and logistics.

If your ship is weak, the Collectors will tear it apart.
If your team is undisciplined, they will die in the vents.
If you fail completely, Commander Shepard will die.

mass effect suicide mission guide to save team squad

This guide is your tactical flowchart. Follow it precisely to achieve the impossible: bringing everyone home alive.

Tactical Analysis: Possible Outcomes

Before we begin, understand the stakes. The mission simulates a real command structure.

Bad intel leads to casualties.

Scenario Omega (Total Failure)

Outcome: Shepard dies. The entire squad dies. The Normandy is destroyed.

Cause: Zero upgrades. Zero loyalty. Joker is the sole survivor, left to mourn over Shepard's coffin in the wreckage.

Scenario Pyrrhic (Partial Success)

Outcome: The Collector Base is destroyed, but Shepard dies in the escape jump.

Cause: You survived the fight, but fewer than 2 squadmates made it out alive. Shepard slips while boarding the Normandy and falls to their death.

Scenario Grim (Hollow Victory)

Outcome: Shepard survives, but the team is decimated. Mordin takes a bullet holding the line. Tali burns to death in the engine room. Garrus is carried off by Seeker Swarms.

Cause: Poor tactical assignments (e.g., asking a Soldier to do a Tech job).

Scenario Golden (The Perfect Run)

Outcome: No casualties. The entire crew survives.

Requirement: 100% Loyalty. 100% Ship Upgrades. Perfect Specialist Assignments. This guide outlines the path to this victory.

Phase 1: The Approach (Ship Upgrades)

The moment you exit the Relay, the Collector Oculus fighters will attack. If the Normandy SR-2 is not upgraded, the hull will breach before you even land.

Heavy Ship Armor (Silaris Armor): Research provided by Jacob.
Failure Consequence: The Oculus laser slices the hull. Jack is instantly killed in the cargo hold.
Multicore Shielding (Cyclonic Barriers): Research provided by Tali.
Failure Consequence: The engine core overloads. A squadmate dies in the explosion (usually Kasumi, Legion, Tali, or Thane).
Thanix Cannon: Research provided by Garrus.
Failure Consequence: You cannot destroy the Collector Cruiser fast enough. It fires back, killing a squadmate (usually Thane, Garrus, Zaeed, or Grunt).

Phase 2: The Infiltration (Vents & Fire Team)

Once inside the base, you need a tech expert to hack the doors via the ventilation shafts (heat hazard) and a leader to command a diversionary fire team.

Role 1: Vent Specialist (Tech Expert)

Safe Choices (Must be Loyal): Tali, Legion, or Kasumi.

Fatal Choices: Thane, Jacob, Garrus. While they have tech skills, they are too slow. They will take a rocket to the head while trying to close the door.

Role 2: Fire Team Leader (Command Experience)

Safe Choices (Must be Loyal): Garrus (Archangel), Miranda (Cerberus Officer), or Jacob (Alliance Corsair).

Fatal Choices: Zaeed (he is a mercenary loner, not a commander), Grunt (too aggressive), or Samara (works alone). If the leader fails, the Vent Specialist dies.

Phase 3: The Long Walk (Biotic Bubble)

You must traverse the Seeker Swarm nests. Conventional shields fail here. You need a Biotic Field to repel the insects.

Role 3: Biotic Specialist

Safe Choices (Must be Loyal): Samara/Morinth (Asari Justicar) or Jack (Subject Zero).

The Trap: Miranda will volunteer, claiming she can do it. She is wrong. While powerful, she lacks the pure biotic endurance of an Asari or Jack. Her bubble will fail at the very end, and the Swarms will carry off one of your squadmates.

Role 4: Fire Team Leader (Part 2)

Safe Choices (Must be Loyal): Garrus, Miranda, or Jacob.

Note: Miranda has unique "plot armor" here and can survive leading this second team even if disloyal, but don't risk it.

Phase 4: The Crew Escort

You find the surviving crew (Dr. Chakwas, Kelly Chambers). They cannot fight. You must decide whether to send a squadmate to escort them back to the ship.

Send an Escort (Must be Loyal): The crew survives. The escort survives.
Send NO Escort: The crew is slaughtered by Collectors on the way back.

Tactical Advice: Send Mordin Solus. He is physically frail and contributes very little to the final "Hold the Line" defense score (see below). Sending him away actually improves the survival odds for the rest of the team.

Phase 5: The Final Battle (Hold the Line)

This is the hidden math that kills most players.

You pick 2 squadmates to fight the Human-Reaper. The rest stay behind to hold the door against the Collector horde.

The Defense Score Algorithm

The game calculates a "Defense Score" for the team left behind. You need an average score of 2.0 or higher to ensure everyone survives.

The Tanks (4 Points): Garrus, Grunt, Zaeed. (These are your anchors).
The Soldiers (2 Points): Thane, Legion, Samara, Jacob, Miranda.
The Weak Links (1 Point): Mordin, Tali, Kasumi, Jack.

The Golden Rule: Leave the Tanks Behind!

Do NOT take Garrus, Grunt, or Zaeed to the final boss. Their high defense score is required to protect the "Weak Links" at the door. If you take Garrus with you, the average score drops, and Mordin or Tali will die holding the line.

Recommended Final Boss Squad: Take Tali, Jack, or Kasumi. They are useless at holding the line but great for the final fight, effectively removing their "low score" from the average calculation.