A cognition thief was a psionicist who specialized in espionage via psionics and was a member of the Hall of Mental Splendor.[2][note 1]


Cognition thieves were psychic spies who specialized in raiding the minds of their targets to rob them of their secret thoughts and even their wits. Their powers were subtle and they appeared inconspicuous, making them highly effective spies.[2]

All known cognition thieves around 1373 DR were trained at the Hall of Mental Splendor in Skullport. The majority continued to work as mercenary spies for that organization, but a few had retired or departed on less friendly terms.[2] Cognition thieves were commonly found in Waterdeep, the city on the land above Skullport.[1]


A would-be cognition thief needed skills in deception, disguise, the gathering of information, and/or picking locks. They also had to be inquisitors who could use their psionic focus to sense deceit in others. Finally, they needed to be able to manifest the power psionic blast.[2]

Most cognition thieves began as psions dedicated to the telepathy discipline, but wilders and other kinds of psion were also possible. They were the only folk capable of the necessary psionic powers, but a few monstrous creatures able to emit a psionic blast also became cognition thieves.[2]


A cognition thief trained in the skills of a spy and of a psionicist. They continued to learn psionic powers, and acquired additional powers of the telepathy discipline. Furthermore, they gained additional powers to read thoughts and use mind probe, and to inflict confusion and insanity upon their foes.[2]


Cognition thieves were all members of the Hall of Mental Splendor, an organization that sold the services of its spies.[2]



  1. The cognition thief is a prestige class for the 3.5-edition of D&D, but refers to the 3rd-edition psionics rules of the Psionics Handbook. All cognition thieves are said to be members of the Hall of Mental Splendor, but this is not actually a prerequisite for taking the class.