The Kull as a species is not psychically active. Even the 'strongest' kull tested for psychic potential scores too low to be of any interest. This makes the kull immune to daemonic possession and the like, and also highly resistant to war corruption, telepathy and similar direct-use psychic powers. They are, however, not immune to assault by warp-spawned abomination - and indeed has few defenses against such attacks. The human population is also screened for psychic potential, but after the coming the of Granite Prince it has been revealed that this screening is somewhat lacking.