Modest (+spa, -atk)
252 HP, 40 Def, 88 SpA, 120 SpD, 8 Spe
An absolute force to be reckoned with. Becomes as bulky as specially defensive Conkeldurr with less EV investment (But less powerful obviously), a Modest nature in order to be able to dish out some pain, and 8 EVs invested in Speed in order to outspeed other Prankster sets (which will either be running 0 or 4 spe EVs) and Taunt them, ruining their strategy, and proceed to take them out with Air Slash. Has worked an absolute charm so far. Priority Roost and Taunt work wonders against stall, too. Beats Skarmory 1 on 1.
I'm going to have to test this set a bit more, but it's working great. Brutalises opponent's non-attacking (or boosting) momentum and hits back hard.