I did some research and found a recent post from BoingK mostly talking about Adaptability Meowscarada, but he also did mention:
Diancie @ Leftovers
Ability: Water Absorb/Earth Eater
EVs: 252 HP / 252 Def / 4 SpD
Relaxed Nature
- Stealth Rock
- Moonblast
- Body Press
- Diamond Storm
Diancie adds rocks, provides good matchups depending on the ability that is chosen, and helps wall some of the strong hitters like Moon and Pao