Jaghatai Khan had been a prisonner of the Webway for tens of thousands of years. Long ago, he had avenged his world by burning the evil kabal that was responsible to the ground. But after his deed had been complete, there was no way back for him. So the Son of the Emperor did what he knew best. He killed. Dark Eldar after Dark Eldar. He butchered them like animals. He may have been a prisoner of the Webway, but he was not locked up with the Eldar, no... they were locked up in there with him.