I've been playing a fair bit of this meta and it's really great fun! I wanted to share a few sets I've been using:
Azelf @ Life Orb
Ability: Levitate
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Knock Off
- U-turn
- Fire Punch
- Explosion
Azelf is rad, really fast with great coverage and power, and Protean Explosion OHKO's most things that don't resist it. Azelf has a lot of other options too, including screens, Stealth Rock, and lots of other coverage options. It is unfortunately very frail however.
Diancie @ Diancite
Ability: Clear Body
EVs: 4 Atk / 252 SpA / 252 Spe
Naive Nature
- Explosion
- Moonblast
- Protect
- Earth Power
Another Explosion user, Mega Diancie has good speed and great mixed offenses + perfect coverage with Moonblast and Earth Power. Protect allows for a safe mega evolution, and allows it to block Fake Out, and Explosion is just a stupidly powerful nuke that can be used to remove threats to your team once Diancie has run its course.
Klefki @ Light Clay
Ability: Prankster
EVs: 248 HP / 252 Def / 8 SpD
Bold Nature
- Thunder Wave
- Reflect
- Light Screen
- Spikes / Magic Coat / some attack
Klefki is a really rad mon in this tier; its typing allows it to switch in on common priority moves like Extreme Speed and Fake Out and threaten the users of those moves with a Thunder Wave, or just set up screens and Spikes. T-Wave is also great to cripple all the fast offensive threats that are running around.
Metagross-Mega @ Metagrossite
Ability: Tough Claws
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Hammer Arm
- Bullet Punch
- Ice Punch
- Thunder Punch
This thing is incredible; so much power with Tough Claws and base 145 attack, and excellent coverage in combination with great speed makes this thing a really dangerous offensive threat. What really sets it apart however is its great bulk that allows it to pretty comfortably take most priority moves.
A lot of common ou stuff is really rad here too; scarf Lando-T, pdef Garchomp, and sash Alakazam are all really solid mons. In my experience priority is king in this metagame; Pokemon like Dragonite and Mega Medicham prey upon the frail, offensive nature of this meta and are dominating forces that every team needs to be ready for. Stall really just isn't viable, offensive mons are just so powerful and versatile that defensive playstyles just generally can't keep up.