Songs of the Damned

Add {B} for each creature card in your graveyard.

Crypt Rats

{X}: Crypt Rats deals X damage to each creature and each player. Spend only black mana on X.

Swamp

Barren Moor

Barren Moor enters the battlefield tapped.
{T}: Add {B}.
Cycling {B} ({B}, Discard this card: Draw a card.)

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

Stinkweed Imp

Flying
Whenever Stinkweed Imp deals combat damage to a creature, destroy that creature.
Dredge 5 (If you would draw a card, you may mill five cards instead. If you do, return this card from your graveyard to your hand.)

Blood Pet

Repository Skaab

Exploit (When this creature enters the battlefield, you may sacrifice a creature.)
When Repository Skaab exploits a creature, return target instant or sorcery card from your graveyard to your hand.

Lurching Rotbeast

Cycling {B} ({B}, Discard this card: Draw a card.)

Blood Celebrant

{B}, Pay 1 life: Add one mana of any color.

Putrid Imp

Discard a card: Putrid Imp gains flying until end of turn.
Threshold — As long as seven or more cards are in your graveyard, Putrid Imp gets +1/+1 and can't block.