Mismagius
Timid Nature (Max Speed, rest in HP and DEF)
*Leftovers*
~Calm Mind
~Taunt/
Will-o-wisp/
Substitute/
Pain Split
~Thunderbolt/
Shadow Ball
~Hidden Power Fighting/
Shadow Ball/
Energy Ball/
Sub, Taunt, PS, and Wisp all have their advantages. Taunt shuts down Blissey (barring Ice Beam). It'll also stop other CMers and SDers. Pain Split is your only recovery move (if you use this, put more EVs into DEF instead of HP). Wisp Allows you to cripple Physical attackers (barring Heracross, Guts Machamp, and Guts Hariyama.
T-bolt is needed to stop Skarm and Cune, unless you use taunt, then go with SB. Then pick a special move and sweep.