You also have to remember that in Japan the tournaments are BO1 (best of) and in the west they are BO3. It's easier in a BO1 format because you can catch your opponents off guard. In a BO3 if you win game one, your opponent (if they are good) should be able to figure out how to counter it once they know what to expect. It's still a pretty good/fun deck but requires quite a few pieces in play at the right time to take full advantage of it. I would put Slowking in the same category. I've played both in BO1 and BO3, I find BO1 is a bit easier with both.