Nice RMT you had there! I had one nitpick though, since you maxed out your Sheddy's Defense and HP I would make it a more stall oriented set, something a little like.
Shedinja @ Flame Orb
252 HP, 252 Def, 4 Sp. Def
Wonder Guard - Only super effective attacks harm this Pokémon
~Rest / Toxic
I'd recommend black sludge but that would violate the item clause, but here is the standard staller set. Sub up, and use dig and protect to stall, then rest to recover damage. The flame orb is a nasty trick to offensive pokemon (especially physical ones) looking to limit your walling with Trick.