Gone, gone, the form of man! Rise the Demon, Etrigan!
That immortal line alone intimates just how mythic the character of Etrigan is, with their alter ego, Jason Blood, going some way in hammering home the same message. First introduced to DC continuity in 1972 by legendary comic book creator Jack Kirby, the Demon has since developed into one of the publisher's foremost supernatural heroes, and would definitely feel right at home in the Injustice-verse.
Could an appearance in Injustice 3 be on the cards? Here's hoping.