Oh god that Cloyster set. I've only faced it once so far as I'm aware, but it totally screwed me the hell over when it flinched my Vaporeon with Rock Blast. My current team would be a little better off but still at serious risk.
Speaking of which, said current team is probably going to have to be retired when Gothitelle actually starts getting the usage it deserves. My team is a Regenerator core, so it NEEDS to switch. Gothitelle would destroy both Amoongus and Slowbro and I'd just be flat out screwed. I might actually have to start running shed shell if it becomes a problem...
So yeah, Gothitelle kind of scares the crap out of me and I'm just glad no one seems to realize how dangerous it is yet. Shadow Tag anything is a stall player's worst nightmare, and I've only gotten more and more stall oriented as the fifth generation has dragged on...
haha well that's the thing about king's rock cloyster, you think you have it walled and then surprise your wall just got flinched! great set, sorry about your vaporeon though :(
and yes, i would highly recommend going the dw route and running shed shell amoonguss. dw players do it for st chandy, but imo goth is a huge threat to your team from the two pokes you've listed. or you could just run sand stall and not care at all because pursuit ttar is the best gothitelle counter out there.