Talonflame, for reasons mentioned in my last post.
Also, I'm very late with this, but everyone who said it was impossible to put up rocks vs. Mega Sableye needs more SR Mold Breaker Excadrill in their lives.
Rocks drill is really niche and Excadrill usually has better things to do than set up rocks (and it's bad at that because it doesn't beat any hazard remover).
Anyways, I think you guys are hyping up Talonflame waaaay too much. Although it will win this round, I just don't think it's anywhere near as influential as you make it to be.
If you can't beat Talonflame or are revenge killed by it, you're a bad Pokemon? Please, go say that to Charizard X, Mega Pinsir, Greninja, Keldeo, Clefable, and probably more, all of which were S rank threats at one point or another and were either revenge killed by it or couldn't beat it. Did Talonflame stop them from being massive threats? No. What about Mega Venusaur in XY? One of the most annoying Pokemon to take down, couldn't beat Talonflame, but was still one of the most successful Megas in XY. How about Mega Scizor, who is probably the best Mega at this point in the meta (and still was for a while before right now)? It almost never beats Talonflame, yet it's still really good and common.
That said, I'm not completely against it - it is a great revenge killer, and does force out a lot of Pokemon. But its presence hardly invalidates anything, and the only teams that have trouble against it are HO and maybe stall if you're running Taunt. Basically, I find it over exaggerated in this thread.