Psyren is an assassin with psychic abilities. Her powers include Compulsion, Telekinesis, Memory Manipulation and Post Cognition. Aside from her psychic powers she is also a master of hand to hand combat making her a deadly foe indeed.
The tiara-like object around her head is a Psionic Regulator. When her emotions get out of control her psychic powers go haywire. The Psionic Regulator helps to control the flow of the excess psionic energy.