The dragon god Tiamat and the most powerful umbral great wyrm made eggs. They gave the eggs to every deity. The eggs gave them all unimaginable power at a price. For while the eggs were in their possession Tiamat was gaining their souls. The God Lamashtu heard of this, but it was too late. The eggs stole all pf their godly essence but Lamashtu cast a spell on all of the eggs that sent the eggs to her. She then nurtured the eggs into dragons and made them servents. The dragon rebeled and Lamashtu took away their godlie power inexchange for spider legs, a starving soul (a souls that needs to power of magic and other souls to survive), and was sent to Geb. They are a promidate race and are usually necromancers. They worship Nethys, Urgathoa, Zon-Kuthon.
The only issue i can see is that most good gods would be... Skeptical at best... Of a gift from Tiamat.