Mass Effect 2 Guide – No One Left Behind Part 2

Well, you made it. Here you stand, in an uncharted part of space, ready to take on the Reapers and their mindless minions. Noone back home is expecting you to come back, but follow Part 2 of our guide below the break to blow through this mission and fly home with all your friends at your side.

For this portion of the guide, I'll be including a reference flow chart that originally appeared in Game Informer and expanded upon by the BSN user Maelon.

Arriving at the Collector Base

Well, it's a nice view, I'll give 'em that.

As you activiate the Omega-4 relay and jump to the endgame, you'll come into a cinematic piece where the Normandy will be fighting off Collector spacecraft while darting through a massive debris field. This is where your ship's upgrades kick in, as there will be three checks throughout the scene, and for each upgrade you did not purchase with resources, a member of your squad will die.

  • Armor Check - A Collector Oculus fires at the Normandy. The Normandy will shrug off the attack with Heavy Ship Armor, but Jack will die without it.
  • Barrier Check - Joker will try and shake off the remaining Oculi in the debris field, and ends up scraping along a large chunk of derelict ship. With the upgraded kinetic barrier, the shielding holds. Without it, an explosion at the core will engulf a squadmate.
  • Gun Check - As you near the base, a Collector Ship will attempt to intercept you. With an upgraded Thanix cannon, you can engage from distance and cripple the ship before flying in to finish it off. However, without the upgrade, you must close distance to fire, causing one member to die along the way.

An Oculus will breach the ship, requiring you to bring a team and engage. The beginning of this fight will take place around the time of the Barrier Check, so any squadmates you bring will not be subject to the Check. Otherwise, who you bring and how long it takes you to kill the Oculus will not effect crew survival.


After crash landing on the base, you devise a plan to split the team to break through initial defenses and rendezvous in the control center of the Collector Base. You'll need to select a Tech Specialist to sneak through the vents and hack the doors open, as well as a leader for the second fire team. Your two choices must be loyal in order for everyone to survive. Your choices that will guarantee survival are:

  • Tech Specialist - Tali, Legion, or Kasumi.
  • Fire Team Leader - Garrus, Miranda, or Jacob

If you choose anyone else, or if either of your two choices from the list are not loyal, your Tech Specialist will catch a bullet to the face and die.

During the mission, your tech specialist will come across 8 barriers that must be opened from the outside, or else the vents will heat up beyond survivability. However, failure here is treated as a "Game Over" and not as a permanent character death.

The Long Walk

After meeting up with the rest of your team, you'll find yourself in a room filled with filled Collector pods. As you watch one victim turned into DNA goo, you'll order your team to open the rest of the pods. This will include the Normandy crew that was kidnapped before. Depending on how many missions you completed between the abduction and arriving at the Collector base, you'll find that either the entire crew, half the crew, or just Dr. Chakwas will have survived. However, this will not impact the achievement.

Tracking the tubes in the room, Shepard finds his next objective. However, the path is filled with Seeker Swarms, requiring a biotic specialist to escort Shepard's squad through. Your choice here must be loyal:

  • Biotic Specialist - Jack or Samara/Morinth

Miranda says that any biotic can handle it, but don't listen to her. If you choose another biotic, then their field will waver - causing one of your team members to be overwhelmed and carried off by the Seekers.


You must also select a team leader for the distraction squad, that will go through a seeker-less tunnel and pull the Collectors' attention away from Shepard's squad. Your ideal choices are the same as the Fire Team Leader from the previous leg:

  • Fire Team Leader - Garrus, Miranda, or Jacob

Interesting note: For this portion, Miranda can be made the Fire Team Leader without being loyal, because she's considered plot-critical for the next portion. However, if you choose Garrus or Jacob, they must be loyal, or else they'll catch a bullet in the gut and die.

Crew Escort

Mordin's a popular choice for this part. You'll see why in a bit.

Before you embark, Dr. Chakwas will point out that the crew won't survive in a fight, and needs an escort to return safely to the Normandy. You can choose let them go alone, but this will result in the crew's death and in failing the achievement. Alternatively, you can send a squad member back with them. This will remove that sqaud member from your roster for the rest of the mission.

For the purposes of this portion, you only need to know that the squad mate will die if he's not loyal. It's best to pick a "weaker" squadmate, such as Mordin or Jack, but we'll get into the reasons for that later. For this part, here's how it will break down:

The Stand

Once you pass The Long Walk, you'll have the Big Baddie ahead of you, and an army of angry Collectors behind you. Miranda tells you to pick a team to go with you, and the rest of the squad will stay behind and hold off the Collectors. For picking your team, you only need to know that a squadmate will survive the boss encounter with you if they are loyal. For the defensive line, this is where finishing everyone's dirty laundry comes in handy.

For this portion, all your squadmates are assigned "Defense Scores" based on their combat abilities - ranging from 0 to 3. A loyal squadmate will have an additional defense point added to their score, bumping the range to 1-4 if you take care of everybody. The chart below will illustrate your team's respective scores:

Out of the squadmates left to hold the line, their defense scores are averaged out to a team based score. If this average score equals or is greater than 2, then the entire line survives. If it's anywhere between 0 and 2, then people will start dying - starting with non-loyal squadmembers and then going in order. Mordin is the first loyal character that will die from a sub-par defense score, and this is why he is often sent to escort the crew.

Now you can see why a weaker squadmate is used for the previous escort choice - it's a numbers game. Since the defensive team is pulled from available members you don't bring with you to the boss, you can remove the weaker links from the defense score. For example, if everyone's loyal, and you send Mordin to escort the crew, you can select Tali and Jack to come with you and you'll have only one member left below the target score of 2.

Maelon goes into further detail over exactly what would happen if you were to fall below this score.

The Final Check


After the final boss is defeated, the world comes crashing down on you and your two squadmates. As Shepard wakes up, he checks on his teammates. At this point, if a squadmate is loyal, they will survive as well. Otherwise, they will die under the rubble.

Shepard and team soon make a break for the Normandy, as the Collector Base is about to either explode or evict all organic material within. If both teammates survive, then Shepard will live as well. However, if one or both teammates die, then Shepard will fall to his death, relying on a crippled Joker to hoist him aboard.

Like The Illusive Man told you, this is a dangerous mission. However, if you follow this guide, then you'll have all your friends back in Mass Effect 3, likely cracking jokes about that one time you decked a reporter.

Back to Part 1