Galrauch

Galrauch, the Great Drake, is an ancient Dragon possessed by the will of the Lord of Change Fateclaw, becoming the first of the Chaos Dragons.

Overview
In the time of Aenarion, when the Elves fought their great wars against the tides of Chaos, the elder race of Dragons fought at their side. These great drakes were the nemeses of the armies of the Dark Gods, diving from the skies upon the scions of Chaos and crushing or incinerating them in their thousands. The might of the Dragons could only be matched by the greatest of Daemons, and the epic clashes between these mighty creatures were events of such magnitude that the mortal warriors could only witness them in awe.

It was during such a battle that Galrauch the Gold Drake came upon Fateclaw, the Lord of Change at the head of a Daemon horde. As Galrauch descended from the heavens like an avenging thunderbolt, the avian Daemon-thing below did nothing more than bare its teeth in a sinister expression of glee. Galrauch’s great jaws snapped shut around Fateclaw’s head, ripping it clean away in a multicoloured spray of ichor. Within a heartbeat, the broken body of the Greater Daemon had dissolved into a scintillating mist that enveloped the exultant Dragon and sank into his flesh.

Galrauch, resplendent in victory, flew high into the air, and the Elf warriors below him raised cries of triumph. But their cheers died away when the Dragon’s body became suddenly wracked by violent convulsions. The mighty drake froze in mid-air, and an evil, iridescent light appeared in its eyes. His scales flowed like water, forming into evil, leering faces that cackled maniacally in praise of Tzeentch. Foul tentacles and wicked spikes emerged from the Dragon’s flesh, and finally the once-noble head of Galrauch split into two all the way down to the base of his neck. Where there was once one head, there were now two, and to the horror of the Elves below, both turned towards their ranks. One head belched dark fire, burning scores of Elves alive, but the other breathed a sorcerous mist that brought horrible mutations and madness. The heads were governed by the same will at first, but soon they started to tear at each other with hatred, a sure sign that the spirit of the great Dragon had not been completely destroyed. The mind of the Lord of Change managed to wrest control of the powerful body once again, but not before the Elves and Dragons had broken the back of the Daemon armies.

Galrauch withdrew from the lands of mortals and slept for centuries at a time, emerging now and then throughout history to wreak havoc on the lands of Elves, Dwarfs and Men. Legend has it that he was the first of the Chaos Dragons, and that many were the dark creatures born of his blood and of his evil sorcery. It was Galrauch who slaughtered King Thurgrim Rockarm and all his kin and sacked their ancient halls. It was he who single-handedly destroyed the city of Languerre de Lac and plunged its ruins into eternal night. Hundreds of noble heroes have tried to slay him, but they have all failed, and their remains hang high in Galrauch’s lair as a testament to the Dragon’s sorcerous might.

Source

 * Warhammer Armies: Warriors of Chaos (8th Edition) -- pg. 56