Here's what I'm using:
Jirachi @ Leftovers
Ability: Serene Grace
EVs: 252 HP / 144 Atk / 112 Spe
Jolly Nature
- Substitute
- Iron Head
- Fire Punch
- Toxic
The speed EVs give you 290 speed, enough to beat neutral max speed Kyu-B and everything below that including jolly Mamo and adamant...