Quote from GumgodMTG »Just want to point out that Night's Whisper is actually functionally different than Sign in Blood. (Night's whisper doesn't target a player).
Quote from ThatRedwood »Night's Whisper could be replaced with Spoils of the Vault. That gives twice as many effects to just find one enchantment or the other, while leaving the card draw that doubles as a combo starter.
Quote from GumgodMTG »piranha marsh is another way to start your combo.
Quote from ThatRedwood »I'm not convinced going into red is worth it.
There are plenty of black cards to start the combo for B, such as Bile Urchin, Death Cultist, Ebony Charm, Shadowfeed. Since you're already running a fair amount of card draw it should be easy to get Cabal Rituals humming beyond their base level of fine, more so since mono-color makes it easier to run things like Barren Moor/Polluted Mire.
I also like how the 1 drop critters can be dropped early. Allowing you a 0 mana way to respond if someone Disenchants in response to the first bloodletting effect. But I guess R can do that too.