I preferring running this:
Greninja @ Life Orb
Naive, 88 Atk / 168 SpAtk / 252 Spe
-Hydro Pump (Scald and Surf are too weak for his "good" base special attack)
-Grass Knot (hits Water/Ground and Electric mons he would normally be walled by)
-Ice Beam (Dragon killing, hits Grass types and makes him neutral to their Grass move if they survive
-U-Turn (muhmentum, but still hits relatively hard thanks to STAB)
The only benefit I see from a straight Timid Special set would be a powerful Hidden Power but getting that perfect IV combination in-game is a cunt. Extrasensory and Dark Pulse aren't that great coverage wise; Psychic STAB only hits Poison and Fighting hard, and the latter is usually frail anyways, while Dark STAB hits Psychics and Ghosts, which are again, really frail. Also he learns Shadow Sneak which will let me rape Aegislash/M-Banette anyway.