Gloomtail may be a large dragon, but Sonic’s dealt with many foes like that. Gloomtail just won’t be able to match Sonic’s killer speed and few can accomplish such a feat. Gloomtail can try to land a solid blow on Sonic, but he’ll already be eating a chili dog in Mexico by that point. Once Sonic gets the 7 Chaos Emeralds, then it’s over. Sonic wins.