Gray wins this. Snorlax isn't much of a threat to an experienced mage like Gray.
Snorlax is a the more experienced fighter and would melt Grey's ice with heat wave. don't see what grey has that can win.
snorlax solos the entire super smash bros. roster.
Gray fights Natsu all the times and is more experienced than any wild pokemon. Snorlax gets gutted like a fish.
Heat Wave and Flame Wheel auto melt a Pokemon when frozen and PP that doesn't count for the Anime or Manga. So it wouldn't be a problem
Anime isn't even canon and Gray can easily decapitate Snorlax. Snorlax is not beating one of FT's strongest mages. This is just classic pokemon wank.