Dark Tongue

The Dark Tongue is the arcane language of the Forces of Chaos. A ritual language, its phoentic runes are the only manner in which the mysteries of Chaos can truly be expressed. It is the native language of daemons and Chaos creatures with the power of speech. The Thousand Sons Traitor Space Marines in particular strive to learn this arcane language for the conjuration of Chaos entities and to bargain with daemons when they are summoned.