The only explicit feat I can think of for Malcador is when he did that psychic shout that could be heard by anyone in a 10km radius, in The First Heretic. And in Flight of the Eisenstein his presence unnerved/upset that one Silent Sister who came with Garro and Cruze (to the point she was trying to back away from him IIRC). And he was still able to use his psychic abilities just fine in her presence. Generally, only the absolute most powerful psykers can override a blank's null field and affect them in the manner they usually affect psykers.
The human appendix. Proof of a higher power. A divine kill switch so to speak.
No one really likes a smartass, but people tend to like a dumbass even less.
Last edited by Chompy Bits; 04-25-14 at 12:18 PM.