Muck Rats

Crypt Rats

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

Hecatomb

When Hecatomb enters, sacrifice Hecatomb unless you sacrifice four creatures.
Tap an untapped Swamp you control: Hecatomb deals 1 damage to any target.

Swamp

Kjeldoran Dead

When Kjeldoran Dead enters, sacrifice a creature.
{B}: Regenerate Kjeldoran Dead.

Order of the Ebon Hand

Protection from white
{B}: Order of the Ebon Hand gains first strike until end of turn.
{B}{B}: Order of the Ebon Hand gets +1/+0 until end of turn.

Initiates of the Ebon Hand

{1}: Add {B}. If this ability has been activated four or more times this turn, sacrifice Initiates of the Ebon Hand at the beginning of the next end step.

Infernal Contract

Draw four cards. You lose half your life, rounded up.

Sewer Rats

{B}, Pay 1 life: Sewer Rats gets +1/+0 until end of turn. Activate no more than three times each turn.

Contagion

You may pay 1 life and exile a black card from your hand rather than pay this spell's mana cost.
Distribute two -2/-1 counters among one or two target creatures.

Dark Banishing

Destroy target nonblack creature. It can't be regenerated.

Wall of Corpses

Defender (This creature can't attack.)
{B}, Sacrifice Wall of Corpses: Destroy target creature Wall of Corpses is blocking.

Bog Rats

Insidious Bookworms

When Insidious Bookworms dies, you may pay {1}{B}. If you do, target player discards a card at random.