He appears to be a human who stands around seven feet tall. His skin is a dark grey. The hair on his head is short and black, no hint of hair on his face or elsewhere. The eyes are yellow and slitted, reminiscent of something reptilian.
Zaerinth was a once a man of what are known to few as the Travelers, a civilization of humans and near-humans that travel between planes, dimensions, and worlds through use of technology and magic. Through his achievements, and the power that was his birthright, Zaerinth ascended to godhood.
He first made himself known on Edora during the demonic invasion. He fought the invading army, but whether it was done out of altruism or eliminating a competitor remains to be seen.