If your character can hypnotize another character, you need to consider a number of factors.

What are the appropriate targets for the hypnosis? Humans, animals?

What is the method of hypnosis? - Line of sight, eye contact, audible tones, scent, etc.

What is the range of the hypnotic effect?

How long does the hypnotic effect last?

How coercive is the hypnotic effect?

How radical are the shifts the power can cause?

How do strong will, psi shields, and/or various other mental states affect this?

Example Characters: Mesmero, Persuasion