I don't think the god card counts, since there are also gods in sci-fi, so both could do that. As for Cthulhu, isn't he both fantasy and sci-fi?
Anyway, I think it would be a draw. Fantasy could use a magic of immense destruction which wipes out all beings and sci-fi could do the same with some hyper advanced technology.
Anyway, I think it would be a draw. Fantasy could use a magic of immense destruction which wipes out all beings and sci-fi could do the same with some hyper advanced technology.