Suicune
Suicune has high defenses, and with a move that heals it back up fully, is a beast. I've been wrecked by this 'mon a lot on Pokemon Showdown, and here's the moveset I recommend.
Suicune @ Leftovers
Ability: Pressure
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
IVs: 0 Atk
- Rest
- Sleep Talk
- Scald/Surf
- Calm Mind
Basically, you can just spam calm mind till you're at max, and rest at low health, and of course use sleep talk while asleep. Then, use Scald/Surf to wreck the opponent. Pressure can be used to pp stall the opponent. Hope I Helped!