From Lexicanum

Karanak is a Chaos Daemon Flesh Hound who is the incarnation of Khorne's vengeance against those who insult Khorne's pride, warriors that break Khorne's creed, and cowards that refuse to shed blood. There is no hiding. Karanak hunts them down across all of space and time. When not hunting, Karanak keeps watch in Korne's throne room.¹

Karanak has three heads, each capable of tracking unlucky prey by different means. The first follows the prey's trail through space, the second tracks the scent through time, and the third, the most dangerous, senses the prey's thoughts.¹

Sources

• ¹:Codex: Chaos Daemons (4th Edition), p.55