Vespin Chloras

 was an archmage during the Age of Arcanum who freed the Betrayer Gods from their prisons. has not appeared on the show.

Background
In ancient Vasselheim, Vespin was a famously masterful, wealthy, and vicious archmage. Inspired by the ascension of the Raven Queen and driven by his hunger, he sought guidance and power from the Betrayer Gods, opening the gates of their prisons and releasing them and their creations into the mortal world. Upon seeing the world, the Betrayer Gods’ need to destroy was replaced by desire to dominate, and their first thrall was none other than Archmage Vespin. The release of those gods led directly to the Calamity.

Following his death, Vespin is believed to be a devil serving at the left hand of Asmodeus, Lord of the Hells.