John Wayne, Gareth Brown.
Nominations:
Excadrill: Seeing Gliscor on teams like Politoad/Thunderus/Tornadus/Starmie/Nattorei is really kind of heartbreaking. In order not to just lose against Excadrill with a non-rain or sun team, teams need Gliscor or Skamory, two of the most exploitable and easily overloadable pokemon in the metagame, for one of which there exists an instant-kill button. Both of which are almost always a Rock Slide flinch away from oblivion. Other checks like Slowbro, Reuniclus, and Tangrowth are sketchy since +2 X-Scissor all but kills all three and Conkeldurr and Azumarill are flimsy and only present a 50/50 standoff where the Excadrill user still stands to lose much less from a mispredict. Things like Garchomp and Landorus are vaguely possible as checks but require severely risky play. It bothers me that players need to run at least one of 2 specific pokemon to really make it a fair game of pokemon and that they need at least one of very few checks to make it a favorable one: with any amount of team support, Excadrill sweeps through its "counters" and, with no team support, it sweeps through everything else. Of course, with a well-built offensive team, it's vaguely possible to get away with 1-2 checks; Sun has proven this by being, overwhelmingly, at the top of the leaderboard and teams like Franky's, PK_Gaming's, or even my own from last period show that it is possible to pressure Excadrill to take advantage of Excadrill offensively. It's only the presence of these teams that keeps me from feeling it overwhelmingly broken, but... I'd definitely like to support its nomination.
Sand Veil + Snow Cloak: This has gotten a lot less popular because of jokes about Cacturne and Glaceon but, honestly, it can't at all be fun to miss against either. Players don't use them because they aren't much good outside of hax and need more misses to function, but two misses with the promise of more against SD Cacturne or Specs Glaceon cannot be fun. While these are rare situations, they should not be a situation at all. I agree that Gliscor is relatively benign, but that's only because it never runs offensive EVs and is only ever used to soften and spread status. But, I'm sure SD-Sand Veil Gliscor could make at least a few players ragequit. Practically, this doesn't have much of an effect on play at all: it only keeps people from spamming bad sets on bad pokemon. As such, it makes a lot of sense to me to make sure those bad sets on bad pokemon never win games. Given its newly mediocre speed tier and the option of so many other, unique dragons beside it, I don't think Garchomp is at all broken beyond Sand Veil: it's solid stats and good STABs and functional -- not at all spectacular relative to pokemon like Thunderus or Terrakion -- sweeping ability let players feel good about abusing its ability, but it's really the ability that people are abusing. In the probable event that my explanations aren't thorough enough or that this doesn't get enough support, I'd like to nominate Garchomp.
Thunderus: Literally a moveslot away from Camerupt being its only counter in a metagame bereft of checks thanks to Ferrothorn, it's far too strong a sweeper. Everything in the world is 2HKO'd by it, it has Nasty Plot, priority Thunder Wave, a better effective speed tier than even Garchomp in generation 4, fantastic typing, and great coverage. It's not impossible to keep from setting up, though it'll often get at least one kill every switch-in in the process. It's only crippled, really, by its Stealth Rock weakness -- which it overcomes with Leftovers -- and its frailty. Though, I think that the main reason why Thunderus is so dangerous isn't so much that it's a scary pokemon, though it is, but that the metagame doesn't reward the use of Scarfers because of Sand Stream and Chlorophyll and that the metagame doesn't really reward the use of pokemon faster than Thunderus because of Nattorei (and Sand Stream and Chlorophyll). I think that if anything were banned or something were adjusted, the metagame could possibly adapt to Thunderus; but, I think that at least one big thing needs to go from the current metagame and I'd be content if that thing were Thunderus.