Kairos Fateweaver is a Lord of Change.
Official Canon Edit
Kairos was cursed by Tzeentch to have two heads; one head speaks the truth, while the other lies. Kairos is capable of seeing the future, but due to the nature of his curse, is unreliable.
TTS Canon Edit
Tzeentch uses Kairos to tell him if he's going to win his next Children's Card Game, if he's not feeling too lazy to ask.