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I was on the fence about whether or not Aegislash was broken since the beginning of this gen. But lately I've realized how blatantly broken it really is. It shaped the metagame around it, made tons of Pokemon like Jirachi, Celebi etc. unviable. You can't make a team without something just for...
Probably pretty late to this thread but I can see why people get upset about Baton Pass. I always thought it would be stupid to do anything about it, until I got a few battles with it myself (ones with good players). In those battles it went either way, me starting up a chain and just plowing...
I'm in favor of banning Swagger or Swagger+Prankster. While it is possible to beat swagplay teams, it's all a coin flip. The nature of how these moves rely on luck is uncompetitive and does not belong in the metagame.
Mega Lucario really needs to, and probably will go. Adaptability Close Combat especially if at +2 is just ridiculous and should have never existed. Not to mention a nice 112 speed tier and many priority options in bullet punch, vacuum wave and extreme speed. Genesect is also just as powerful...
Mega Charizard X is a huge problem if it can get up a DD (which isn't very hard against Skarmory), as long as rocks are up it just OHKoes your whole team with a combo of flare blitz and outrage. I'd recommend maybe something like Azumarill as it can take on both of its stabs, and hits back hard...