So, as an older player returning to magic (Started back a month or so after Theros release) I really like the idea of devotion and Black seems to support that the best currently.
This is my POST-RTR rotation look at MBD and the direction it may take. Obviously when Khans is released this will probably change slightly.
Thoughtseize - Doesn't need any explanation, probably the best black card in standard.
Gnarled Scarhide
- A nice 2/1 for 1 that can apply some early pressure in the event you don't have a TS in your opening hand. I think early aggression was one thing missing from MBD because even a T2 pack rat wasn't much of a threat until T3/T4 depending on mutavault drops. Even better, if you draw this guy mid/late game he can be bestowed onto on of your fliers to get in for extra damage.
Brain Maggot - It's no pack rat in our 2 spot, but a mini-thoughtseize with a body isn't a bad thing.
Herald of Torment
- Coming in to replace NV Specter. You lose 1 devotion and the exile ability, but he does have the added benefit on being able to bestow.
Master of the Feast - 5/5 for 3, a decent trade off in place of DD's 6/6 for 4. They can't keep him back by sac'ing creatures, but be wary of how much card advantage you let them get. Brain Maggot helps alleviate this quite a bit.
Mogis's Marauder - Probably the card I'm most on the fence about including in the deck. He can sneak through quite a bit of damage if you drop him T4 after a MotF. Of course vs other Black decks he loses his usefulness. May consider swapping this out for more removal or perhaps something like
Stab Wound
Removal Spells - Most of these are self explanatory. Extinguish All Hope is basically a board wipe for my opponent and safe for me since all my creatures, except Gary, are enchantments. If Gary is actually on the board I WANT to kill him so I can whip him back.