Demoniacal

a.
  1. Pertaining to, or characteristic of, a demon or evil spirit; devilish; as, a demoniac being; demoniacal practices.
  2. Influenced or produced by a demon or evil spirit; as, demoniac or demoniacal power.
  3. resembling or suggesting possession by a demon; as, demoniac energy.
  4. in a murderous frenzy as if possessed by a demon.