Name: Ennis Tremellyn
First Appearance: Marvel Two-in-One (vol. 1) #49 (Mar. 1979): "The Curse of Crawlinswood"
Super? (Has Super Powers/Special Abilities/Technology): Yes
Number of Appearances: 1
Ennis Tremellyn worshipped the god Ahriman and apparently derived some legitimate power from this being as well. Presumably the fact that he worships Ahriman (a Zoroastrian deity) means that Ennis Tremellyn is himself Zoroastrian. But further investigation into this story is warranted to determine whether Zoroastrian themes actually play a part in the story, or whether perhaps Ahriman name was simply borrowed and used as the name of Ennis Tremellyn's deity without any attempt to allude to the Ahriman of real-life Zoroastrian belief.
Contemporary Zoroastrians regard Ahriman as essentially the devil. So anybody who worships Ahriman would not be a normative, orthodox Zoroastrian but could said to be an apostate, or affiliated with an Ahriman-worshiping set. In Christian circles, this would be the equivalent of worshiping Satan (Lucifer).
Suggested links for further research about this character and the character's religious affiliation: