Here's a core that I've been experimenting with:
Thundurus (M) @ Life Orb
Ability: Defiant
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Wild Charge
- Knock Off
- Sky Drop
- Protect
Gyarados @ Gyaradosite
Ability: Intimidate
EVs: 108 HP / 252 Atk / 148 Spe
Adamant Nature
- Waterfall
- Earthquake
- Dragon Dance
- Protect
Thundy takes care of Venusaur, Amoongus, and Top, and it benefits from Intimidate.
Skymin typically doesn't want to switch in on Thundy either, for fear of Thunder Wave.
Sky Drop also gives Gyarados a free turn to set up Dragon Dance, and with the EVs listed, he is 1 point slower than Thundy after a Dragon Dance, allowing for a potential double attack. Mega Gyarados is deadly after a Dragon Dance, and Waterfall/Earthquake gives it excellent coverage.
It deals with Lando-T, Heatran, and Rotom-W without a second thought.
Unfortunately, both Pokemon are weak against Terrakion - Close Combat 1HKOs Gyara, and Rock Slide does heavy damage to Thundy. Terra is also immune to Sky Drop, since it weighs over 200 kg. However, after Dragon Dance, Gyarados outspeeds Terra, allowing for an easy 1HKO.
This core is also quite weak to being burned: while the vast majority of WoW users will go down without much of a fight, it is quite possible for, say, a Gourgeist to survive the Sky Drop and subsequent attack from Gyarados.
What do you guys think?