Suggested by Sonic Fin Fang Foom has a lot of raw power but it will be difficult for him to land a direct hit on Zadkiel. Zadkiel has enough raw power to destroy many Ghost Riders before he was brought down. He can fly as well so Foom doesn’t have that advantage over him. It’s a case where speed is crucial and Zadkiel should be able to stay one step ahead of the dragon the whole time. Zadkiel wins.
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I don’t doubt Fin Fang Foom’s powers and might, but when you face off against a being close to the eternal, which is what Zadkiel is, only one outcome for one fighter is certain above all: Death.
Agreed, Zadkiel is definitely just on a higher level at this point. He would be able to completely crush Foom