Work in progress torment-style cube (most cards are black)

rough breakdown:

Sultai: Proliferate

Grixis: Madness / Graveyard

Mardu: Sacrifice / Tokens

Abzan: Proliferate / Sacrifice

Jund: Sacrifice / Proliferate

Esper: Proliferate

Lifegain / Vampires

Proliferate / Counters

Sacrifice-y-Graveyard-y / Zombies

Graveyard / Madness

Madness / Vampires

Sacrifice

Proliferate / Sacrifice / Thallids

Monoblack Devotion