Mass Effect 2 Tali: Treason Guide (2026)

The Tali: Treason loyalty mission is one of Mass Effect 2’s most emotionally charged side quests, sending you through the Valhallan Threshold to the Quarian Migrant Fleet for a trial that can reshape Tali’s future. This walkthrough-style guide covers every major combat stretch, all collectible locations, and the key dialogue decisions you’ll face—from the first conversation with Tali on the Normandy to the final return after the verdict.

Mission summary, rewards, and what you’ll be doing

The mission takes place in the Valhallan Threshold, beginning when Tali’s loyalty case becomes active and escalating into a full operation aboard the Alarei. Your objectives include getting through multiple firefights while searching for loot, making choices in front of the Admiralty Board, disabling a Geth console to uncover the truth, and then deciding whether to present evidence that could save Tali—or destroy her father’s legacy in the process.

Rewards for completing the loyalty mission include 750 XP, the Energy Drain power, and research progress tied to Geth Shield Strength and Tech Damage. You’ll also receive 15,000 mission credits, with an additional 30,000 found credits across the run. Resource rewards list 2,000 Palladium.

Unlocking the loyalty mission and first talk with Tali

Tali’s loyalty mission becomes available after you recruit her via “Dossier: Tali,” and after you speak with her aboard the Normandy at least once. There’s a small dependency chain: her mission won’t start until you’ve unlocked the loyalty missions for Jacob, Miranda, Jack, Mordin, Grunt, Garrus, and Samara. Some of those can be skipped depending on which squadmate you have, but the mission still won’t appear until the required loyalty structure is in place. Once it’s unlocked, Kelly will let you know when you pass by the Galaxy Map.

When you finally talk to Tali about it, she explains that her people have accused her of treason. The situation is especially painful because, even when she’s considering herself, Tali has long prioritized her loyalty to her people. She’s being forced back to the Migrant Fleet to defend herself—despite not even knowing what the charges are. Regardless of your stance, she marks the flotilla’s location on the Galaxy Map so you can go.

Travel to the Migrant Fleet

The Quarian Migrant Fleet is currently located in the Vallhallan Threshold. To reach it, use the Galaxy Map like you would for any standard destination: open the Normandy’s galaxy map, select the Vallhallan Threshold, then land at the system’s Raheel-Leyya location where the Migrant Fleet is orbiting near the binary stars. Once you touch down, the mission flow picks up immediately.

Recommended loadout

Squad tactics:
- For both story and practical reasons, the squadmate from the Reaper IFF mission, Tap to Reveal, is the top pick here because their tech expertise—including effective AI Hacking—fits the mission’s structure very well.
- If you’re not using that option, Garrus is the next best choice since his Overload ability is particularly useful.
Unique dialogue:
- The Tap to Reveal squadmate unlocks a large amount of mission-specific dialogue that later matters in Mass Effect 3.
- If you gave Veetor to Cerberus during Freedom’s Progress, bringing Miranda allows you to trigger a special, very specific dialogue moment.

Go to the hearing aboard the flotilla

As the Normandy docks, Tali contacts the Quarians on the ship you’re about to enter. They request identification, and she recites a Quarian phrase that confirms her status. If you played Mass Effect 1, you’ll recognize a familiar detail: the ship has the same last name as Tali’s earlier identity. It was the craft she was born on before her pilgrimage. After she returned, she joined the Neema and adopted a changed name.

Upon landing, you’re greeted by Tali’s friend, Captain Kar’Danna.

Choose “I owe Tali a great deal” to gain +2 Paragon Points.

Kar’Danna explains that Tali is being charged with treason for sending active Geth back to the fleet. Tali insists that while she did send Geth components to her father as part of a research project, none of it was active or functional. The Admiralty Board doesn’t accept that distinction, and until the trial occurs, Kar’Danna orders Tali not to leave the ship she’s currently on.

If you brought the Tap to Reveal squadmate, you’ll find plenty of unique dialogue during this section and more opportunities to earn morality points.

Using the Renegade Interrupt grants +5 Renegade Points.
After that:
- Select “Calm down” for +2 Paragon Points.
- Select “It’s called Tap to Reveal” for +2 Renegade Points.
If you’re not in the interrupted path above, you can still choose “Calm down” for +2 Paragon Points and select “It’s called Tap to Reveal” for +2 Renegade Points.

When the standoff needs to end, you’ll be asked to pick from several responses:

“You’ll have to shoot us both” (Charm) awards +5 Paragon Points.
“If it acts up, I’ll kill it” (Intimidate) awards +5 Renegade Points.
“I’ll do this for Tali” awards +2 Paragon Points.
“Tap to Reveal, go back to our ship” lets you switch to a different squadmate.

After regaining control, move down the corridor to meet Shala’Raan, another Quarian familiar to Tali. Their history runs deep, but Shala’Raan has been forced to recuse herself, meaning Tali has no allies among the people deciding her fate. On top of that, Tali has been stripped of her ship surname, vas Neema, and is being tried under vas Normandy. The silver lining is legal: because Shepard is tied to the ship Tali is currently associated with, you’re bound to represent her at the trial.

At that point, you can respond with either:

“I’m honored” for +2 Paragon Points.
“This is a terrible idea” for +2 Renegade Points.

The trial itself happens in a rare, open area within the flotilla that can fit a large crowd, with an appropriately formal atmosphere. After Shala’Raan’s opening remarks, the hearing begins. Before it moves far, Koris—one of the ruling council—interrupts and objects immediately. The objection can be framed either around a human representing Tali (with Shala’Raan noting Koris shouldn’t have altered Tali’s name to match your ship), or around the Tap to Reveal squadmate (with Shala’Raan noting Koris is second-guessing the captain of the ship you’re on).

Shepard is then asked to speak for Tali. Any choice works, but two options provide morality points:

“It is my pleasure” (Charm) gives +5 Paragon Points.
“Look at her record” (Intimidate) gives +5 Renegade Points.

After further argument, you respond that Tali isn’t treasonous because the items she sent were inert. That’s when Koris reveals the bombshell: the Geth have taken over the Alarei—the ship her father served on—traumatizing Tali while the hearing is already underway.

Your response can yield additional morality points:

“We need to help” (Charm) awards +5 Paragon Points.
“You’ve got a lot of nerve!” (Intimidate) awards +5 Renegade Points.

From here, retaking the Alarei becomes the priority. It’s necessary to protect the flotilla and to investigate what’s being claimed about Rael’Zorah, Tali’s father. You can answer with:

“We must. For Tali’s sake” for +2 Paragon Points.
“If it proves her loyalty” for +2 Renegade Points.

Board the Alarei and prep for the investigation

After the trial, you reunite with Tali. You can also talk with members of the Admiralty Board in the plaza, plus two Quarians you’ve met earlier. Doing this is strongly recommended because it can award morality points and provide background on Quarian politics that affects not only this hearing, but also later events.

At minimum, revisit Shala’Raan for extra information and more morality points:

“You went too far” for +2 Paragon Points.
“Thanks. Will it help?” for +2 Renegade Points.

Beyond the other Admirals, you can speak with Veetor, the frightened Quarian introduced earlier during Freedom’s Progress. If you released him to Cerberus at that time, he’s visibly nervous. If you bring Miranda with you, he may even react with horror.

If you didn’t send Veetor to Cerberus, you can depart with “I hope you feel better” for +2 Paragon Points.

Kal’Reegar is also present if he survived the final assault on Haestrom in “Dossier: Tali.” You may also want to speak again with Captain Kar’Danna, since he can clarify some of the flotilla’s logistical troubles.

If you brought the Tap to Reveal squadmate, you can trigger even more dialogue at this moment. Admiral Xen takes special interest in them, while Shala’Raan, Gerrel, and Koris gain an additional dialogue choice. Select “Admirals’ infighting,” then choose the exclusive option that appears in the lower-left corner of the Dialogue Wheel. It won’t change anyone’s minds, but it does lead to some memorable reactions from the Admirals.

When you’re done, leave through the door near Admiral Koris and walk to the end of the hallway. Speak with the Shuttle Guard to start the flight over to the Alarei, beginning your investigation and the fight to cleanse it of Geth presence.

Retake the Alarei: combat flow and collectible locations

Once you regain control on the Alarei, take the brief pause to prepare your weapons. The moment you move into the next space, the room beyond the door becomes an active engagement. Expect typical Geth Troopers along with Geth Hunters—enemies that can cloak and use shotgun fire—so plan for close-quarters threats.

When you enter, sprint ahead to secure cover. Geth Troopers fill the room, and additional enemies will spill out of the door ahead and from the left side. With the exception of the Geth already posted when you arrive, most hostile forces come through the left door. That makes it workable to advance and use the right side of the bunk beds as cover, pushing to clear the doorway quickly.

Med Kit — 100 credits: front-left corner, or directly left of the entry door.
Laptop — 1,500 credits: back-right corner of the room, located on a desk in orange-lit space.
Laptop — 1,800 credits: same general location as the previous laptop, but positioned to the left of the Quarian Log in the middle.
Power Cells — to the right of the exit door among assorted crates.

Continue into the next hallway by first going through the door beside the window and into a side room. On the table to the left sits a Repair Drone. You don’t need to interact with it, but using it reveals extra information about how Tali handled sending Geth parts to her father.

Terminal — 4,200 credits: standing in the doorway of the side room, immediately to your right.
Medical Station — 100 credits: standing in the doorway again, directly ahead on the wall.
Terminal — Geth Shield Strength: exit the side room, face forward, then enter the door ahead in the corner to find this terminal.

Back in the hallway one more time, locate a Quarian Log on the right side near the door to the next area.

As you enter the following room, keep your weapon ready and stay in cover. A Geth Hunter will come down the distant stairs and attack. Remove it, then search the room.

Laptop — 1,800 credits: right corner of the room, in the corner closest to the entry door.
Laptop — 2,100 credits: right corner of the room, in the farthest corner from the entry door.
Wall Safe — 4,200 credits: check the desks at the bottom of the stairs where the Hunter entered from. It’s next to a Quarian Log on the desk below.

At the top of the stairs, turn left into the kitchen where another fight begins. This one is tougher because the Geth are entering from two separate doors, leading to a double influx of Troopers and Hunters. The Hunters are especially aggressive; their stealth tech can make them vanish enough to close distance and deal heavy damage. Once the area calms down, search for more supplies.

2,000 Refined Palladium: in the corner directly left of the entryway.
Med Kit — 100 credits: just right of the exit doorway in the back-left corner.
Wall Safe — 3,000 credits: when you enter through the exit doorway, look right at the corner where the wall meets the area to spot it easily.

In this kitchen space, you can activate a Wall Console that triggers another scene involving Tali. For the console’s response:

“That’s a bad idea” for +2 Paragon Points.
“That’s a worthy promise” for +2 Renegade Points.

The follow-up options differ, but the upper-right selection results in +2 Paragon Points, while the lower-right choice provides +2 Renegade Points.

Proceed into the next room where you’ll end up on a balcony overlooking a lower level. A staircase drops down to your right. Geth forces arrive from straight ahead on the lower floor door, and also from a balcony to your left that you can’t reach. The left-side attackers have a habit of killing your squad without you noticing, so keep an eye on your team’s status and angles. Hunters will also try to climb the stairs after you. When they appear, commit resources and keep them from getting too close.

Laptop — 2,400 credits: go down the stairs; it’s on the right-side bench.
Laptop — 1,800 credits: on the table to the left of the exit doorway.
Med Kit — 100 credits: from the higher laptop location, turn left and go to the back corner. It’s on crates between two white-lit windows.

You can also find one last Quarian Log on the right side of the exit doorway.

Through the doorway, the mission delivers a major emotional moment: Tali discovers the body of her father.

Use the Paragon Interrupt to hug her and earn +5 Paragon Points.
If you skip the Paragon Interrupt, you can choose either:
- “This wasn’t his choice” for +2 Paragon Points.
- “We’ll destroy the geth” for +2 Renegade Points.
After viewing Rael’s message to Tali, respond with:
- “He did what he could” for +2 Paragon Points.
- “The geth cut him off” for +2 Renegade Points.

When the scene ends, be sure to check a side room packed with items.

Wall Safe — 1,500 credits: corner immediately left of the entry door.
Med Kit — 100 credits: on crates to the right of the Wall Safe.
Wall Safe — 2,700 credits: back-right corner above a single white crate.
Power Cells — 100 credits: on top of a gray crate on the right-hand wall.

Disable Geth Console and learn the truth

After finishing the exploration, return to the hallway and climb the stairs into the Alarei’s final room. On entry, you’ll find a Model Flotilla Ship on the right-hand desk in front of you, and a Laptop worth 3,000 credits on the left-hand desk in front of you.

Across the window area, expect two Geth Hunters plus a Geth Prime. The Prime is a heavyweight you last fought back on Haestrom, and it’s equipped with Shields and Armor. Because this room has limited cover, you’ll need to retreat smartly and improvise as the fight unfolds.

WARNING: Interacting with the Quarian Console here will immediately send you back to the trial on the Rayya. Before you do so, make sure you’ve collected the Model Flotilla Ship.

When you’re ready, use the Quarian Console at the back of the room to learn what really happened. Rael did reactivate full Geth on the Alarei, but he kept Tali from being implicated by controlling what she was able to send. After the evidence is revealed, you can respond for morality points:

Choose “He wanted to keep his promise” for +2 Paragon Points.
Choose either “That’s what we needed” or “That sounded bad” for +2 Renegade Points.

Tali explains that while this proof would clear her personally, it would also completely ruin her father’s reputation. She begs you not to use it during the trial.

Return to the trial on the Rayya

After that console sequence, you’re transported back to the Rayya. The Admiralty Board debates the plan to exile Tali posthumously, since she’s absent. Return to the trial late, then pick one of the following to open the next dialogue:

“You should pardon Tali” for +2 Paragon Points.
“You could have waited” for +2 Renegade Points.

You’ll then face the incredibly consequential decision: whether to present the evidence against Tali’s father, or use another approach to resolve the charges. The outcomes are as follows:

“We have no evidence” results in Tali being exiled for sending Geth components to the Migrant Fleet. Even so, she’s willing to accept it to keep everything stable. This still ensures Tali’s Loyalty and gives you +30 Paragon Points.
“Yes. Here is the evidence” presents the Alarei recording to the Admiralty Board. This clears Tali of her charges, but the experience traumatizes her, making her Disloyal and awarding you +30 Renegade Points.
The Charm option “I don’t need evidence” has Shepard use Tali’s prior behavior as proof and argue that the Admiralty Board doesn’t actually care about Tali. The board is trying her instead of listening to her about the Geth. This clears her charges, secures Tali’s Loyalty, and gives you +30 Paragon Points.
The Intimidate option “You’re wasting our time!” makes Shepard threaten to leave, then call out the hidden agenda behind the trial of the woman who protected the Citadel from the Geth. This clears her charges, secures her Loyalty, and awards +30 Renegade Points.
“[Rally the crowd]” becomes available only if Veetor wasn’t sent to Cerberus after Freedom’s Progress and Kal’Reegar survived “Dossier: Tali.” It also doesn’t require Persuasion. When selected, Shepard tells the crowd that the Admiralty Board cares about war with the Geth—not about Tali. Veetor and Kal join in, defending her and threatening to exile themselves if the board goes through with it. This clears Tali’s charges, secures Tali’s Loyalty, and awards you +30 Paragon Points.

Before leaving the Rayya, speak with everyone one last time. Their responses will shift based on your final choice at the trial, and they’ll each offer morality points in the usual Dialogue Wheel locations (upper-left and lower-left). A few exceptions stand out:

Shala’Raan only offers morality points if you chose “We have no evidence” and Tali was exiled. That makes the option the biggest Renegade-leaning choice overall. Shala’Raan will be furious, but Tali defends your decision during the hearing.
Veetor and Kal’Reegar only give Paragon points if both are alive and you selected “[Rally the crowd].” That makes “[Rally the crowd]” the option that yields the most Paragon points overall.
Captain Kar’Danna at the airlock never offers morality points, but he will be infuriated if his former crewmate ends up exiled.

After wrapping up conversations, head back to the Normandy either via the on-screen prompt or by using the airlock door near Captain Kar’Danna.

Back on the Normandy: where to talk and what changes

CIC: talk to Joker for a comment on Tali’s trial.
Crew Deck: talk to Kasumi if you did not present the evidence against Tali’s father; Thane also gains new dialogue.
Engineering: Tali receives new dialogue reflecting the aftermath of her loyalty mission.

If you brought the Tap to Reveal squadmate along and you’re aiming to romance Tali, plus you want the most favorable endgame condition, you’ll need to set aside some side quests after the main story wraps. Romance can’t be fully continued right away without impacting the Suicide Mission timing, so planning extra tasks later is the key to keeping everything on track.

Want more assistance for Mass Effect 2? The guide also points you toward pages covering Legendary Edition changes, how-to help, key choices and consequences, romance options, the walkthrough, and side quests.

Up next: Thane — Sins of the Father.