Mol'Zhar the Merciless is an avernic demon famed for his loyalty to Zaros, and the lack of mercy he shows his foes. During Children of Mah, he is encountered during Kharshai's memory of the betrayal of Zaros, in which he is present in The Empty Throne Room eagerly awaiting the sentencing of three traitors. After Zamorak and his followers arrive to kill Zaros, he attempts to defend him by engaging in combat with another demon. His fate after this is unknown.
- He uses the same in-game model as Yk'Lagor the Thunderous.