“These are the ones. The unfortunate ones. The lucky ones.”
Cerra (or the Oracle, as some of the Inquisitor’s staff call her) is the Inquisitor’s seer, a psyker with not-insignificant powers of prophetic sight. While her visions are rarely easy to comprehend, they are most of the time chillingly accurate – their interpretation is just often difficult or outright impossible until the vision has already come to pass. And indeed, sometimes the visions are not of the future, but of the past – of things related to what is happening or about to happen. Cerra is surprisingly old for a psyker, especially an unsanctioned one – this can mostly be attributed to her removal from field duties and her carefulness to all things related to the Warp, she only uses her powers in dire need or when the Inquisitor specifically requests them.
The seer is a short, aging woman, usually dressed up in simple grey robes, her eyes covered up with a grey cloth. She does have her eyes, but she prefers to keep them covered, especially whenever she is trying to use her sight.
She was the one who picked the five acolytes out of the billions of possible names.