I'm on the fence about {empty the pits}. One good counter spell or a {drown in sorrow} if I don't have an obelisk and I've thrown away my graveyard for nothing. {Corpseweft} limited to only creatures, but it should get our early enough that hopefully they don't have the mana to counter. Also I can choose to make the zombies beefy by exiling more creatures (which is why the deck was so creature heavy before).