Crypt Rats

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

Monstrous Carabid

Monstrous Carabid attacks each combat if able.
Cycling {B/R} ({B/R}, Discard this card: Draw a card.)

Dark Ritual

Lurching Rotbeast

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

Swamp

Horror of the Broken Lands

Whenever you cycle or discard another card, Horror of the Broken Lands gets +2/+1 until end of turn.
Cycling {B} ({B}, Discard this card: Draw a card.)

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.)

Mnemonic Wall

Defender
When Mnemonic Wall enters the battlefield, you may return target instant or sorcery card from your graveyard to your hand.

Blood Celebrant

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

Songs of the Damned

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

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Golgari Brownscale

When Golgari Brownscale is put into your hand from your graveyard, you gain 2 life.
Dredge 2 (If you would draw a card, you may mill two cards instead. If you do, return this card from your graveyard to your hand.)

Grave Scrabbler

Madness {1}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)
When Grave Scrabbler enters the battlefield, if its madness cost was paid, you may return target creature card from a graveyard to its owner's hand.

Street Wraith

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
Cycling—Pay 2 life. (Pay 2 life, Discard this card: Draw a card.)

Architects of Will

When Architects of Will enters the battlefield, look at the top three cards of target player's library, then put them back in any order.
Cycling {U/B} ({U/B}, Discard this card: Draw a card.)

Tortured Existence

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