Shiala: the asari commando Saren traded to the Thorian

Shiala was an asari commando and a powerful biotic who spent nearly two hundred years as an acolyte of Matriarch Benezia, and who ended up sold to a plant. Saren Arterius gave her to the Thorian on Feros in exchange for the Prothean Cipher, took what he needed out of her head, and then ordered the geth to burn the creature with her still inside it. She is also the one person on record who broke Sovereign's indoctrination and lived.

How did Shiala end up inside the Thorian?#

Saren needed the Prothean Cipher to understand the vision from Eden Prime, the Thorian had it, and the price the Thorian named was an asari it could absorb. Saren gave it Shiala.

She had come to that point by following someone she admired. For nearly two centuries Shiala had been an acolyte of Matriarch Benezia, respecting her judgement and her biotic skill, and she went aboard Sovereign with many of Benezia's other followers when the matriarch set out to guide Saren onto a gentler path. Benezia failed and was indoctrinated. Shiala became one of Saren's thralls in the same moment, and from then on she served him willingly.

The trade itself was a merger rather than an execution. Shiala was absorbed into the Thorian and shared its single consciousness, and from inside it she used her biotics to take hold of the Cipher and transfer it into Saren's mind. Once he had it, he left her where she was and ordered the geth to destroy the creature, which would have killed her and denied Shepard the Cipher in one move.

Zhu's Hope#

By the time Shepard's team reaches the Thorian's lair, the creature is producing clones of Shiala to speak through. They are biotics as well, and they attack the squad while it works to kill the Thorian.

Killing it frees her. Shiala comes back to herself and tells Shepard what Saren did, how Benezia was reduced to a slave to his cause, and what the Cipher actually is. Knowing the vision leads to the Conduit, she reaches into Shepard's mind and hands the Cipher over directly, with the warning that this is a considerable gift and that understanding it will take time.

Then Shepard has to decide what she is. Spared, she stays on Feros and commits to helping the colonists. Executed, it is on the reasoning that Shiala switches sides too often, and she does not fight it: she kneels and takes a round in the back of the head from the Spectre she has just helped.

If she lives, she can be found on later visits outside the Borealis, next to what used to be the entrance to the Thorian's lair. Her mood there depends on how the colony fared. With Zhu's Hope intact she is ashamed of what was done to the colonists and intends to make it right. With too many of them dead, she vows to stay until every survivor has left.

Her survival is worth stating plainly. Shiala is the only individual known to have thrown off Sovereign's indoctrination without killing herself, and the likely reason is that the Thorian took her over in turn. When the plant died, her mind came back.

Illium, two years on#

Spared on Feros, Shiala turns up on Illium in 2185, working through a medical contract the colonists of Zhu's Hope had signed, and Shepard can offer to negotiate with the company for her.

The Thorian left marks. In the months after her exposure her skin pigmentation shifted to green, the same colour as her clones, and her biotics became unstable. She also describes dreams about her time inside the creature that she does not enjoy having.

Her manner in that conversation is set by what happened on Feros. If the colony lived and Shepard helps her, she makes a pass at the Commander, suggesting that maybe sometime, when she is not organising a colony and Shepard is not doing whatever Shepard does, before smiling and stroking Shepard's arm on the way out. If the colony died, the flirtation is gone entirely. She says instead that she is a commando and does not know how to help people, and that she will try anyway.

Still fighting#

If both Shiala and the colony came through, Shepard gets an email from her during the Reaper War about Zhu's Hope fighting again, this time against Reapers rather than geth.

The Thorian is dead, she confirms, but its spores are still in their bodies and the colonists remain connected on some level. In a battle that connection lets them sense each other and act with one mind, ignoring pain, so that untrained settlers fight like veteran commandos. She admits she does not know what it will do to them long term and wonders whether they ought to separate for their own safety.

She also says something harder. She believes she is still indoctrinated, and she can remember Sovereign's voice in her head from the day she walked willingly to the Thorian. Her link to the people of Zhu's Hope is louder, and it drowns the Reapers out. She has not forgotten that Shepard spared her, and she tells the Commander that the colonists are leaving Feros and will fight alongside the fleet when the moment comes.