Set'tyra'ex is a Gaunt Summoner of Tzeentch, known as the Tongueless Lord. He is bound by his true name by Archaon and forbidden to speak, because his voice was stolen by Archaon as punishment for unwillingness to voluntarily serve him. After that the sorcerer turned his wrath upon the Mortal Realms, taking from his victims what had been taken from him, drawing endless pleasure from seeing his enemies struck mute.
During the Age of Chaos the Tongueless Lord often stood before an unnaturally silent battlefield, the agony of the dying and the rage of their killers painted upon faces with mouths open in soundless screams. Archaon has often used his talents on his own lords, ordering the wizard to steal their voices if he grows tired of what they say. Should they continue to displease the Everchosen, the Gaunt Summoner calls upon his repertoire of mutating magic to warp their flesh, all in utter silence, save the deep rumble of Archaon’s cruel laughter.