I am currently planning on using
Clawitzer in my Standard Offensive Team in Pokemon Y. For me, personally I would invest the evs and ivs into it's special attack and speed rather than defenses reason being; mono water typing and decent natural bulk. With that bulk I would not worry about scarfing it since it can take in some hits. I would choose to use Choice Specs with a Timid nature or Modest. But this is my idea of an offensive one it is still good for a tank.
Clawitzer @ Choice Specs
Trait: Mega Launcher
EVs: 4 HP / 252 Sp.Atk / 252 Spe
Timid
or Modest Nature
- Aura Sphere
- Water Pulse
- Dark Pulse
- Ice Beam (Over Dragon Pulse to take care of pesky grass types)