The Cult's field operative. The most dangerous kind of true believer: kind, sincere, and completely committed to something that might end the sector as everyone knows it.
Early 30s. Travels light — one bag, one blaster, one weathered copy of Cult scripture she clearly hasn't opened in years. She has the quiet confidence of someone who has already made peace with consequences. Bright-eyed in a way that reads as either warmth or mania depending on the light.
The signal is the Way-consciousness of the Procyon sector itself — something so vast and ancient that the Ur could only gesture at its outline. Activating it would not destroy the sector. It would awaken it. Every person who has ever struggled to touch the Way would feel it open beneath them. She has seen glimpses in deep meditation. She is certain.
She is wrong about one thing: what the signal does to the Hantu gate. She doesn't know about the gate. The Remembrancer does, and hasn't told her.
Sera approaches with the careful warmth of someone who knows she's asking for trust she hasn't earned. She won't lie — about her goals, about the Cult, about the risks as she understands them. She will omit what the Remembrancer hasn't told her. This creates a situation where the crew trusts her more than they should, or exactly as much as they should, depending on whether they ask the right questions.
The question Wren tells the crew to ask her: "What's on the other side of the Hantu gate?" Watch her face when she answers. She doesn't know. The crew will see that she doesn't know. That's the moment they realise the Remembrancer is withholding from his own operative.
When the crew discovers what the Remembrancer knows and didn't tell Sera, her reaction is the campaign's emotional pivot. She is devastated, then furious, then — depending on who the crew is — either doubles down or reconsiders everything.