>>31913213That's why I suggested scald. Not as powerful as STAB launcher water pulse or hydro pump, but the burn chance is great and with M.Blastoises solid 120 base defense as this makes him extremely tough to K.O. on the physical front.
The "breaker" moves are all the other pulse and aura moves, plus ice beam: dragon pulse, aura sphere, dark pulse and ice beam. Go with either dark pulse or ice beam depending on what coverage your team needs. After that just go with a modest nature and go all in on his HP and special attack EVs with the leftovers going to either one of his defenses and you've got a fairly solid tank.
Just never lead with it. M.Blastoise is better used as a late game cleaner.
