Quoted By:
The best move-set depends on what tier you're in.
For OU or VGC rain teams, Thunder, Rest, Surf/Hydro Pump, Ice Beam. Perish Song and Heal Bell are interesing options, you may want to replace Surf or Thunderbolt for one of those moves.
In NU, however, it's completely different. A specially defensive, or even a bulky Dragon Dance set, seem to be the best sets it can run.
