Mass Effect 3 Walkthrough Part 2: Thessia, Cronos Station and the Ending

This is part 2 of our Mass Effect 3 walkthrough for the Legendary Edition. It picks up after Priority: Rannoch and covers the DLC missions, Thessia, Horizon, Cronos Station, the final battle in London and the ending choices. It also explains how your war assets decide the ending.

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The whole series

Where the DLC fits

All three story DLCs are built into the Legendary Edition. They open after Priority: The Citadel II and must be done before Priority: Cerberus Headquarters, the point of no return.

• Leviathan: starts with Leviathan: Dr. Bryson on the Citadel. A detective-style hunt for the being that may explain where the Reapers came from. It adds war assets and useful lore for the ending. Good to play before Thessia or right after.
• Omega: help Aria T'Loak take back Omega from Cerberus. It is a long combat DLC and adds war assets. Play it any time in this stretch.
• Citadel: Shore Leave: a fun, light DLC with your whole crew, plus a big party. Most players save it for last, just before Cronos Station, so every squadmate is recruited and romances are settled.

Priority: Thessia

Do your open side missions first. Thessia is a key story beat and it closes off some side quests.

1. Land on Thessia, the asari homeworld. Take Liara if you can, and Javik if you have him: both get strong scenes here.
2. Fight through the city to the Temple of Athame. Watch for Banshees: they teleport close and grab you, so keep your distance and focus them down.
3. Inside the temple, use the Prothean beacon to find a hidden Prothean VI. It knows what the Crucible still needs.
4. Kai Leng attacks. He has strong shields and a Cerberus gunship backs him up. Stay in cover, strip his shields with tech or biotic powers, and deal with the troops he brings.
5. No matter how well you fight, this mission ends badly. It is scripted. Don't reload trying to "win" it.

Priority: Horizon

1. Track Cerberus to Sanctuary, a refugee facility on Horizon, the colony you visited in ME2.
2. Fight Cerberus troops and Reaper creatures inside. You learn what Cerberus really did with the refugees.
3. If Miranda survived ME2 and you helped her during the game, she plays a big part here.
4. The mission ends with the location of the Illusive Man's base: Cronos Station.

Now is the time to finish everything: side missions, scanning, crew chats, Omega, Leviathan and Citadel: Shore Leave. Once you start the next mission, you cannot go back.

Priority: Cerberus Headquarters (Cronos Station)

1. The Normandy forces its way into Cronos Station. Fight through Cerberus troops, including Phantoms (fast, deadly up close) and Atlas mechs.
2. Part of the base shows recordings about the Lazarus Project that brought Shepard back in ME2.
3. Find the Illusive Man's office and the VI data.
4. Final fight with Kai Leng. He keeps his shields up and dashes around the room while troops pour in. Keep moving between cover, kill the extra troops so they don't flank you, and use heavy weapons or strong powers when his shields are down.
5. You learn the last piece of the Crucible puzzle, and the fleets head to Earth.

Effective Military Strength (EMS)

Before the final mission, check the war room terminal. Your Total Military Strength is the sum of every war asset you gathered.

• In the original 2012 release, a Galactic Readiness rating (raised by multiplayer) cut that number down to your Effective Military Strength.
• In the Legendary Edition, Galactic Readiness is gone. Your total strength is your effective strength. The required amounts were rebalanced so you can reach the best results from single-player alone.
• Higher strength means more ending options at the Crucible, more of Earth surviving, and better outcomes for your crew. The most famous reward, Shepard surviving in one ending, needs a very high score.
• Guides disagree on the exact Legendary Edition numbers, so I won't quote one. In practice: do almost every side mission, the Rannoch peace, the DLCs and a good amount of scanning, and you will be in the top range.

Priority: Earth (London)

1. Your shuttle is shot down by a Hades cannon. Fight to it and take it out.
2. Reach the Forward Operating Base. This is your last chance to talk to everyone: squadmates, allies from your choices, and old friends who survived. Take your time here. These are the goodbye scenes.
3. Pick your final squad and push through ruined London. Expect Banshees, Brutes and Marauders in heavy waves.
4. At the missile battery, hold your position against wave after wave until the missiles fire. Use the high ground, focus fire on Banshees and Brutes first, and revive your squad fast.
5. Make the final run to the Conduit beam, the way up to the Citadel.
6. On the Citadel, you meet Anderson and the Illusive Man. With high Paragon or Renegade reputation, you can talk him down instead of fighting it out.

The ending choices

At the end, Shepard faces the Catalyst. The Extended Cut, included in the Legendary Edition, adds more scenes and an epilogue for each choice. The main options are:

• Destroy (red): wipe out the Reapers. The blast also kills all synthetic life, which means the geth and EDI. With very high strength, there is a short scene that hints Shepard lived.
• Control (blue): Shepard takes control of the Reapers and sends them away from the fight. Shepard does not survive in human form.
• Synthesis (green): merge organic and synthetic life into one. It only appears when your strength is high enough. Shepard does not survive.
• Refuse: added in the Extended Cut. Reject the Catalyst, or shoot at it. The war is lost in this cycle, and the epilogue shows the next cycle using what you left behind.

With low strength you get fewer options, and the outcome for Earth and your crew is worse. Each choice fits a different idea of what Shepard fought for. Pick the one that fits your Shepard.

Tips for this part

• Make a hard save before Priority: Cerberus Headquarters. Then you can try another ending without replaying the whole game.
• Play Citadel: Shore Leave last. The party scenes are better with the full crew.
• Upgrade and mod your best guns before Cronos Station. The London waves are the hardest fights in the game on higher difficulties, and Cronos leads straight into them.
• Don't rush the FOB. Many people skip the goodbye chats and regret it.

My take

The ending caused a huge fight online in 2012, but the Extended Cut fixed most of what bugged me. For me, the real ending is the last hours with the crew: the FOB chats and the Citadel party. I went Destroy on my first run and still think about Synthesis. Which ending did you pick, and would you change it?

FAQ

What is the point of no return in Mass Effect 3?

Starting Priority: Cerberus Headquarters on Cronos Station. After it, the game goes straight to Earth and the ending. Finish side missions and DLC before that.

How do I get the best ending in Mass Effect 3 Legendary Edition?

Raise your war assets as high as you can: side missions, Rannoch peace, the genophage cure handled well, DLC missions and scanning. With very high strength, Destroy gives the scene where Shepard may have survived.

Do I need multiplayer for the good ending?

No. The Legendary Edition has no multiplayer and no Galactic Readiness. Single-player war assets are all that count.

Can I beat Kai Leng on Thessia?

No. You can damage him, but the mission is scripted to end with him escaping. You get your real fight with him on Cronos Station.

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