Gyarados and theme decks mostly.
Wow... You really dont know what Shuppet can do lol. My Shuppet has NEVER lost to LuxChomp in a premier rated tournament and rarely loses to it at the league. Shuppets also beaten Mother Gengar with Tombs and a 2-2 Mewtwo Lv.X line (2/3 times), Donphan, (as you already said) G-Dos, BlazeChomp (pretty much any non-Dialga SP deck in general) and numerous rogue decks. That (and many more decks Im sure) is what Shuppet beats.:smile: