Ravenous ghoul (Mazchna)

The Ravenous ghoul appears at Fairy ring CKS near the mushroom patch west of Canifis when the player is on a Slayer challenge assigned by Mazchna or Achtryn. To activate the challenge, the player be near the ring and must contact Mazchna or Achtryn using an Enchanted gem. The monster will then appear in the centre of the ring (as if it were using the ring) and attack the player.

Other drops
Always drops bones; unknown if it ever drops anything else (no reports of other drops yet).