Bulky? Oh I Love bulky.
Wow.. that sounded creeperish.. OK! Time for the answer.
Use this -
Ferrothorn (M) @ Leftovers
Trait: Iron Barbs
EVs: 128 HP / 60 Atk / 160 Def / 160 SDef
Sassy Nature (+SDef, -Spd)
- Power Whip
- Gyro Ball
- Stealth Rock
- Leech Seed
The Ev's and nature give him equal defending stats, and a good load of HP for Bulk, while enough attack to actually put a dent in a few opponents, and Power Whip and Gyro Ball for more power due to the lack of alot of attack Ev's and Natures, while using Leech Seed to constantly gain health back, and sometimes even force switches for Stealth Rock Damage.