Some core ideas for you balance nerds.
Budget Pdon (Volcanion) @ Leftovers
Ability: Water Absorb
EVs: 252 HP / 4 SpA / 252 SpD (don't know what's the right EV)
Sassy Nature
- Flamethrower
- Earthquake
- Rest
- Sleep Talk
Kyurem-Black @ Rocky Helmet
Ability: Terravolt
EVs: 252 HP / 252 Def / 4 SpD
Impish Nature
- Iron Head
- Roost
- Hone Claws
- Substitute / Fusion Bolt
All of you need to realize that Pdon's typing + Ability synergises with SO much typing combination, that's why it's used so much (actually, Pdon has excellent stats BUT typing IS a major part of why it's good). This is similar. Screw Avalugg, Chansey or whatever defensive staples. These two things wall almost anything because both have considerable amount of bulk AND excellent typing combination.
Another idea is to pair Volcanion with regular Fire/Flying Zard Y because Fire/Ground with Water immunity pairs excellently with Fire/Flying.