I'll spare you a long intro, onto the team immediately.
Banette @ Focus Sash
Brave
Insomnia
252 Attack / 252 HP / 4 Sp Def.
~ Trick Room
~ Destiny Bond
~ Taunt
~ Shadow Claw
It doesn't get much more obvious than this. Focus Sash ensures I get Trick Room up, if there is no priority/weather...