Gravestorm

At the beginning of your upkeep, target opponent may exile a card from their graveyard. If that player doesn't, you may draw a card.

Infernal Darkness

Cumulative upkeep—Pay {B} and 1 life. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
If a land is tapped for mana, it produces {B} instead of any other type.

Eaten Alive

As an additional cost to cast this spell, sacrifice a creature or pay {3}{B}.
Exile target creature or planeswalker.

Bone Shards

As an additional cost to cast this spell, sacrifice a creature or discard a card.
Destroy target creature or planeswalker.

Worms of the Earth

Players can't play lands.
Lands can't enter the battlefield.
At the beginning of each upkeep, any player may sacrifice two lands or have Worms of the Earth deal 5 damage to that player. If a player does either, destroy Worms of the Earth.

Spoils of Evil

For each artifact or creature card in target opponent's graveyard, add {C} and you gain 1 life.

Defiler of Flesh

Menace
As an additional cost to cast black permanent spells, you may pay 2 life. Those spells cost {B} less to cast if you paid life this way. This effect reduces only the amount of black mana you pay.
Whenever you cast a black permanent spell, target creature you control gets +1/+1 and gains menace until end of turn.

Mutilate

All creatures get -1/-1 until end of turn for each Swamp you control.

Urborg Justice

Target opponent sacrifices a creature for each creature put into your graveyard from the battlefield this turn.

Morbid Opportunist

Whenever one or more other creatures die, draw a card. This ability triggers only once each turn.

Dead of Winter

All nonsnow creatures get -X/-X until end of turn, where X is the number of snow permanents you control.

Oubliette

When Oubliette enters, target creature phases out until Oubliette leaves the battlefield. Tap that creature as it phases in this way. (Auras and Equipment phase out with it. While permanents are phased out, they're treated as though they don't exist.)

Artificer's Hex

Enchant Equipment
At the beginning of your upkeep, if enchanted Equipment is attached to a creature, destroy that creature.

Protection Racket

At the beginning of your upkeep, repeat the following process for each opponent in turn order. Reveal the top card of your library. That player may pay life equal to that card's mana value. If they do, exile that card. Otherwise, put it into your hand.

Shakedown Heavy

Menace
Whenever Shakedown Heavy attacks, defending player may have you draw a card. If they do, untap Shakedown Heavy and remove it from combat.

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature.

Burakos, Party Leader

Burakos, Party Leader is also a Cleric, Rogue, Warrior, and Wizard.
Whenever Burakos attacks, defending player loses X life and you create X Treasure tokens, where X is the number of creatures in your party.
Choose a Background (You can have a Background as a second commander.)

Braids, Arisen Nightmare

At the beginning of your end step, you may sacrifice an artifact, creature, enchantment, land, or planeswalker. If you do, each opponent may sacrifice a permanent that shares a card type with it. For each opponent who doesn't, that player loses 2 life and you draw a card.

Helldozer

{B}{B}{B}, {T}: Destroy target land. If that land was nonbasic, untap Helldozer.

Kokusho, the Evening Star

Flying
When Kokusho, the Evening Star dies, each opponent loses 5 life. You gain life equal to the life lost this way.

Necropotence

Skip your draw step.
Whenever you discard a card, exile that card from your graveyard.
Pay 1 life: Exile the top card of your library face down. Put that card into your hand at the beginning of your next end step.

Vilis, Broker of Blood

Flying
{B}, Pay 2 life: Target creature gets -1/-1 until end of turn.
Whenever you lose life, draw that many cards. (Damage causes loss of life.)

Vogar, Necropolis Tyrant

Menace
Whenever another creature dies during your turn, put a +1/+1 counter on Vogar, Necropolis Tyrant.
When Vogar dies, draw a card for each +1/+1 counter on it.

Transgress the Mind

Devoid (This card has no color.)
Target player reveals their hand. You choose a card from it with mana value 3 or greater and exile that card.

Sickening Dreams

As an additional cost to cast this spell, discard X cards.
Sickening Dreams deals X damage to each creature and each player.

Underworld Dreams

Whenever an opponent draws a card, Underworld Dreams deals 1 damage to that player.

Braids, Cabal Minion

At the beginning of each player's upkeep, that player sacrifices an artifact, creature, or land.

Creeping Bloodsucker

At the beginning of your upkeep, Creeping Bloodsucker deals 1 damage to each opponent. You gain life equal to the damage dealt this way.

Bloodletter of Aclazotz

Flying
If an opponent would lose life during your turn, they lose twice that much life instead. (Damage causes loss of life.)

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Phyrexian Obliterator

Trample
Whenever a source deals damage to Phyrexian Obliterator, that source's controller sacrifices that many permanents.

Fleshbag Marauder

When Fleshbag Marauder enters, each player sacrifices a creature.

Avatar of Woe

If there are ten or more creature cards total in all graveyards, this spell costs {6} less to cast.
Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
{T}: Destroy target creature. It can't be regenerated.

Coffin Queen

You may choose not to untap Coffin Queen during your untap step.
{2}{B}, {T}: Put target creature card from a graveyard onto the battlefield under your control. When Coffin Queen becomes untapped or you lose control of Coffin Queen, exile that creature.

Bone Dancer

Whenever Bone Dancer attacks and isn't blocked, you may put the top creature card of defending player's graveyard onto the battlefield under your control. If you do, Bone Dancer assigns no combat damage this turn.

Ghoulcaller Gisa

{B}, {T}, Sacrifice another creature: Create X 2/2 black Zombie creature tokens, where X is the sacrificed creature's power.

Bloodghast

Bloodghast can't block.
Bloodghast has haste as long as an opponent has 10 or less life.
Landfall — Whenever a land you control enters, you may return Bloodghast from your graveyard to the battlefield.

No Mercy

Whenever a creature deals damage to you, destroy it.

Phyrexian Dreadnought

Trample
When Phyrexian Dreadnought enters, sacrifice it unless you sacrifice any number of creatures with total power 12 or greater.