Ezekyle Abaddon, more commonly known as Abaddon the Despoiler, is the Warmaster of Chaos, the former First Captain of the Sons of Horus Legion and now absolute Master of the Black Legion, and rumoured to be the clone-progeny of Warmaster Horus.

He is the most powerful Warmaster of all, successor to his Primarch, and blessed by all four of the Gods of Chaos. Despite being the Warmaster of Chaos, Abaddon has refused giving himself fully over to the Ruinous Powers as the Daemon Primarchs have, as this would limit his existence beyond the Eye of Terror and push his ultimate vengeance against the Imperium beyond his grasp.