Tyranitar @ Choice Scarf
Ability: Sand Stream
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Stone Edge
- Pursuit
- Superpower
- Crunch
Ok so there are a few primary problems with this team: one, Weavile, has already been mentioned and is pretty self-explanatory. Another I see is Zard Y (Latios is a shit switch-in, especially without Roost, and Mega Houndoom can revenge if it's already Mega'd and Zard has some chip damage, but Doomer can struggle to get a Mega off against offensive teams). Also, if Mega Bro gets one CM, for example after Jirachi kills something with Iron Head, it straight up wins. Finally, Gengar, while it certainly has checks, pretty much gets a kill every time it comes out then switches out for free.
So ScarfTar is my solution. Although it fails to outspeed Weavile, this mon doesn't do any ridiculous damage back unless it has Low Kick, which is much less popular than Pursuit right now. Obviously it checks Zard Y and Pursuit traps Gengar to keep it from running rampant all it wants. It isn't exactly the best Mega Bro check in the world, but it's something I guess. Put Toxic on Amoong or somethin idk :/ T-Tar also takes care of Defoggers, which is nice for Mega Houndoom, since it appreciates hazard damage to wear down its checks and counters, and Sand helps weaken them too. Speaking of which, Sand doesn't affect this team too much, since two are immune, one is a Regen mon, and another is relatively frail anyway, definitely gets OHKOed by a lot of stuff.
Whoops I wrote an essay n_n