This deck features heavy amounts of hand and board control, along with the most powerful late game creatures white and black has to offer. Combine this with utility low-cost creatures and some great planeswalkers, and you have one mean deck. Thoughtseize and Brain Maggot control the hand, Dakra Mystic controls draw quality, and the array of removal controls the board for the bombs to carry you to victory.
Creatures
Blood Baron of Vizkopa - Such a powerful creature. Can turn a game around on his own.
Brain Maggot - Messing with someone's hand is a great way to gain an advantage. You've got to be very smart about what to exile as it's easily removed, but this little guy can ruin the opponent's game plan.
Dakra Mystic - Probably my favourite card from the new set. There is so much power in this one drop it's absurd. It's not ideally played on turn one, but a little bit later when you've got the mana to use its ability. It can deny key cards from your opponent and also give you card advantage in the form of quality.
Desecration Demon - He's a big guy. Deal with him or lose.
Obzedat, Ghost Council - Another powerhouse. Life gain for stability and evasion from many forms of removal.
Planeswalkers
Ashiok, Nightmare Weaver - Great against a lot of decks right now. The exile is very relevant against control and dredge, and you can often steal one of their best creatures when facing Monsters or Mono-Black.
Elspeth, Sun's Champion - Everyone knows how good she is now, so there isn't need to go into much detail. Wipes big creatures in a bind or floods the board with little guys she can make bigger. Awesome.
Instants, Sorceries, and Enchantments
Banishing Light - Versatility makes this a great form of removal
Bile Blight - Does work against aggro, opposing Pack Rats, and Mutavault.
Detention Sphere - Again, versatility. Also deals with all the Pack Rats if they're out of Bile Blight range.
Devour Flesh - Helps against hex proof and creatures with protection. Also good against aggro as the downside is negligible.
Hero's Downfall - Instant speed removal to deal with creatures and planeswalkers.
Thoughtseize - Takes threats out of hand before they are an issue.
Lands
Max amount of temples for scrying to keep card quality where you want it. Just over half the lands come in untapped so you can stay on curve where you need to, and the Mana Confluence gets you any colour if you're having mana troubles. A couple shocks would be beneficial, but I'm not going to buy any with only a few months left for them in standard.
Sideboard
1x Bile Blight - One more comes in against mono-black for the added chance of getting one when you need it. Also comes in against any sort of aggro or token decks.
1x Dispel - Used against control, Boros Burn, and Mono-Black if you want extra protection for your creatures.
3x Fiendslayer Paladin - Comes in against any form of aggro, as well as Boros Burn, since they can't target it and he's a constant source of life-gain.
2x Lifebane Zombie - For taking out anything big when it comes to Monsters.
2x Negate - Mainly for control or burn. This over more Dispel for the added coverage of planeswalkers and enchantments.
2x Nightveil Specter - Comes in against control, Mono-Black, and Mono-Blue as you could play potentially anything you exile. Also as a wall against aggro.
3x Sin Collector - Control, Burn, Mono-black.
1x Ultimate Price - Extra removal whenever you want it. Can hit most big things in standard (Stormbreath, Master of Waves, Desecration Demon, Polukranos, Brimaz, etc) while costing less mana than Hero's Downfall.