Stream of Acid

Destroy target land or nonblack creature.

Curtains' Call

Undaunted (This spell costs {1} less to cast for each opponent.)
Destroy two target creatures.

Venser's Journal

You have no maximum hand size.
At the beginning of your upkeep, you gain 1 life for each card in your hand.

Shizo, Death's Storehouse

{T}: Add {B}.
{B}, {T}: Target legendary creature gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)

Altar's Reap

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Rain of Tears

Relentless Rats

Relentless Rats gets +1/+1 for each other creature on the battlefield named Relentless Rats.
A deck can have any number of cards named Relentless Rats.

Arcane Encyclopedia

Attrition

{B}, Sacrifice a creature: Destroy target nonblack creature.

Phyrexian Tower

{T}: Add {C}.
{T}, Sacrifice a creature: Add {B}{B}.

Despoil

Destroy target land. Its controller loses 2 life.

Marrow-Gnawer

All Rats have fear.
{T}, Sacrifice a Rat: Create X 1/1 black Rat creature tokens, where X is the number of Rats you control.

Icequake

Destroy target land. If that land was a snow land, Icequake deals 1 damage to that land's controller.

Aspect of Lamprey

Enchant creature you control
When Aspect of Lamprey enters, target opponent discards two cards.
Enchanted creature has lifelink.

Dark Remedy

Target creature gets +1/+3 until end of turn.

Desecrated Earth

Destroy target land. Its controller discards a card.

Befoul

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

Maw of the Mire

Costly Plunder

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards.

Akroma's Memorial

Creatures you control have flying, first strike, vigilance, trample, haste, and protection from black and from red.

Abnormal Endurance

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Thornbite Staff

Equipped creature has "{2}, {T}: This creature deals 1 damage to any target" and "Whenever a creature dies, untap this creature."
Whenever a Shaman creature enters, you may attach Thornbite Staff to it.
Equip {4}

Dark Bargain

Look at the top three cards of your library. Put two of them into your hand and the other into your graveyard. Dark Bargain deals 2 damage to you.

Dark Ritual

Ashnod's Altar

Rancid Rats

Skulk (This creature can't be blocked by creatures with greater power.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Bad Moon

Aspect of Gorgon

Enchant creature
Enchanted creature gets +1/+3 and has deathtouch. (Any amount of damage it deals to a creature is enough to destroy it.)

Swamp

Piper of the Swarm

Rats you control have menace.
{1}{B}, {T}: Create a 1/1 black Rat creature token.
{2}{B}{B}, {T}, Sacrifice three Rats: Gain control of target creature.

Culling the Weak

As an additional cost to cast this spell, sacrifice a creature.
Add {B}{B}{B}{B}.