Durin is a posthumous overarching antagonist in Genshin Impact. He was a dragon created by the alchemist Rhinedottir, also known as "Gold". After the cataclysm from five hundred years ago, Durin started to attack Mondstadt, until he was killed by Dvalin and his corpse remained in Dragonspine. (https://genshin-impact.fandom.com/wiki/Durin)