Plan is to Polymorph a Lingering Souls token into an Emrakul, the Aeons Torn (which I believe to be the best polymorph target at the moment) although against some match-ups Blightsteel Colossus or Progenitus might be better, I would rather include them in the SB then in the MD.
The plan is simple, the execution of it might not always be so simple, I would aggressively use Silence, Remand and Explore to time walk your opponent, and don't be afraid to block with lingering souls tokens to stave off the very aggressive decks.
Pentad Prism is used as both mana fixing and ramp, since the deck plays relatively little lands, getting to 4 mana for the polymorph (or 5 if you want to silence as well) might not always happen on turn 4.
Spoils of the Vault and Clutch of the Undercity act as extra copies of Polymorph, where Spoils can find other pieces as well (like Lingering Souls) and Clutch can get rid of an annoying permanent when you're in a pinch.
Let me know what you think, play with it and tell me if you'd change anything, I'm always interested in hearing other people's opinion.
EDIT: I've put Pure Intentions in the 'maybe' pile as a try-out for the sideboard to combat Liliana of the Veil, she's the most annoying thing about the Jund match-up and I can't really add the more mainstream Obstinate Baloth. Other then that it also protects my combo pieces from Thoughtseize or Inquisition of Kozilek and even from Blightning (although I haven't seen a lot of those around recently).The cards I'm most likely to cut would be 1 or 2 Path to Exile.
