Fenrir was a pure blooded Fenrir, inheriting the full might of his Mythical ancestor who also happened to be a Deity. Thus, the bloodline he inherited was that of a Mythical being that also allowed him to control divine energy.
It was incredibly powerful, and yet, on a universal scale, it was middling. That was before he got some upgrades inside Abaddon, and that would have eventually helped him surpass his supposed bloodline limits!
But what might happen to a beast capable of controlling divine energy if they hibernate inside a place called Arch-Heaven? Probably a lot of cool things, but Lex would never find out, because when Fenrir went to sleep he was not affected by the divine energy inside Arch-Heaven - instead, he was affected by the feedback from his bond to Lex.
