Armor of Dusk (The Graveyard Trees #2) by Jess Galaxie:
 
The final installment following Feathers of Dawn has higher stakes, features more fluff and more violence, and concludes the epic love story of Asith and Dradevai.

Armor of Dusk is perfect for Dungeons & Dragons lovers!

Asith Evourin has finally found his long-lost father and saved him from a facility harvesting dragons, but at a cost. His partner, Dradevai, stayed behind to rescue more dragons, and Asith is no closer to finding them than they were a year ago. With no leads on where they are or if they’re safe, Asith struggles to enjoy life in the Graveyard Trees, the city of dragons, and pushes his family away.

Everything changes after Asith reluctantly accepts a lesson about magic from his father. He gains confidence in his ability to cast magic and suddenly retrieves a lead on Dradevai’s location. But along the way, Asith must struggle to remain unseen as a wanted criminal, trust people he hardly knows, and face a villain who will stop at nothing to profit off the abuse of dragons.

Can Asith achieve peace between the Sterling dragons and the people of Cairn?
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