The Dray, the draconic race who dwell far beneath the scorched surface of Athas, owe their fearsome form to a transformation wrought ages ago upon the band of humans who then served under Dregoth. However it was not only the bodies of his people that the Dread Lord saw fit to alter to his liking, but also their hearts and minds. This was achieved long before the physical transformation, when he fashioned for them a new religion, one which places himself at the centre of a cosmic drama in which they would play a vital part.
This is a companion discussion topic for the original entry at http://www.athas.org/articles/dray-religion