Crypt Ghast

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever you tap a Swamp for mana, add an additional {B}.

Noxious Gearhulk

Menace
When this creature enters, you may destroy another target creature. If a creature is destroyed this way, you gain life equal to its toughness.

Mutilate

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

Priest of Forgotten Gods

{T}, Sacrifice two other creatures: Any number of target players each lose 2 life and sacrifice a creature of their choice. You add {B}{B} and draw a card.

Dark Ritual

Liliana Vess

+1: Target player discards a card.
−2: Search your library for a card, then shuffle and put that card on top.
−8: Put all creature cards from all graveyards onto the battlefield under your control.

Arcane Lighthouse

{T}: Add {C}.
{1}, {T}: Until end of turn, creatures your opponents control lose hexproof and shroud and can't have hexproof or shroud.

Tetzimoc, Primal Death

Deathtouch
{B}, Reveal this card from your hand: Put a prey counter on target creature. Activate only during your turn.
When Tetzimoc enters, destroy each creature your opponents control with a prey counter on it.

Harvester of Souls

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever another nontoken creature dies, you may draw a card.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Plaguecrafter

When this creature enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.

Killing Wave

For each creature, its controller sacrifices it unless they pay X life.

Ravenous Chupacabra

When this creature enters, destroy target creature an opponent controls.

High Market

{T}: Add {C}.
{T}, Sacrifice a creature: You gain 1 life.

Undertaker

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

Command Beacon

{T}: Add {C}.
{T}, Sacrifice this land: Put your commander into your hand from the command zone.

Magus of the Coffers

{2}, {T}: Add {B} for each Swamp you control.

Sol Ring

Gisa, Glorious Resurrector

If a creature an opponent controls would die, exile it instead.
At the beginning of your upkeep, put all creature cards exiled with Gisa onto the battlefield under your control. They gain decayed. (A creature with decayed can't block. When it attacks, sacrifice it at end of combat.)

Viscera Seer

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

Skull Collector

At the beginning of your upkeep, return a black creature you control to its owner's hand.
{1}{B}: Regenerate this creature.

Vampiric Rites

{1}{B}, Sacrifice a creature: You gain 1 life and draw a card.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Gray Merchant of Asphodel

When this creature 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.)

Costly Plunder

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

Disturbed Burial

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Return target creature card from your graveyard to your hand.

Fortuitous Find

Choose one or both —
• Return target artifact card from your graveyard to your hand.
• Return target creature card from your graveyard to your hand.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Detection Tower

{T}: Add {C}.
{1}, {T}: Until end of turn, your opponents and creatures your opponents control with hexproof can be the targets of spells and abilities you control as though they didn't have hexproof.

Black Market

Whenever a creature dies, put a charge counter on this enchantment.
At the beginning of your first main phase, add {B} for each charge counter on this enchantment.

Campfire

{1}, {T}: You gain 2 life.
{2}, {T}, Exile this artifact: Put all commanders you own from the command zone and from your graveyard into your hand. Then shuffle your graveyard into your library.

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Return target artifact card from your graveyard to your hand.

Nyx Lotus

Nyx Lotus enters tapped.
{T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Defile

Target creature gets -1/-1 until end of turn for each Swamp you control.

Ayara, First of Locthwain

Whenever Ayara or another black creature you control enters, each opponent loses 1 life and you gain 1 life.
{T}, Sacrifice another black creature: Draw a card.

Sarevok, Deathbringer

At the beginning of each player's end step, if no permanents left the battlefield this turn, that player loses X life, where X is Sarevok's power.
Choose a Background (You can have a Background as a second commander.)

Kokusho, the Evening Star

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

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Massacre Wurm

When this creature enters, creatures your opponents control get -2/-2 until end of turn.
Whenever a creature an opponent controls dies, that player loses 2 life.

Blood for Bones

As an additional cost to cast this spell, sacrifice a creature.
Return a creature card from your graveyard to the battlefield, then return another creature card from your graveyard to your hand.

Disentomb

Return target creature card from your graveyard to your hand.

Massacre Girl

Menace
When Massacre Girl enters, each other creature gets -1/-1 until end of turn. Whenever a creature dies this turn, each creature other than Massacre Girl gets -1/-1 until end of turn.

Erebos, God of the Dead

Indestructible
As long as your devotion to black is less than five, Erebos isn't a creature. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
Your opponents can't gain life.
{1}{B}, Pay 2 life: Draw a card.

Mortuary Mire

This land enters tapped.
When this land enters, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.

Puppeteer Clique

Flying
When this creature enters, put target creature card from an opponent's graveyard onto the battlefield under your control. It gains haste. At the beginning of your next end step, exile it.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Ogre Slumlord

Whenever another nontoken creature dies, you may create a 1/1 black Rat creature token.
Rats you control have deathtouch.

Palace Siege

As this enchantment enters, choose Khans or Dragons.
• Khans — At the beginning of your upkeep, return target creature card from your graveyard to your hand.
• Dragons — At the beginning of your upkeep, each opponent loses 2 life and you gain 2 life.

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Netherborn Altar

{T}, Put a soul counter on this artifact: Put your commander into your hand from the command zone. Then you lose 3 life for each soul counter on this artifact.

Scrap Trawler

Whenever this creature dies or another artifact you control is put into a graveyard from the battlefield, return to your hand target artifact card in your graveyard with lesser mana value.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Yahenni, Undying Partisan

Haste
Whenever a creature an opponent controls dies, put a +1/+1 counter on Yahenni.
Sacrifice another creature: Yahenni gains indestructible until end of turn.

Myr Retriever

When this creature dies, return another target artifact card from your graveyard to your hand.

Disciple of Bolas

When this creature enters, sacrifice another creature. You gain X life and draw X cards, where X is that creature's power.

Swamp

Nightmare Unmaking

Choose one —
• Exile each creature with power greater than the number of cards in your hand.
• Exile each creature with power less than the number of cards in your hand.

Village Rites

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

Recover

Return target creature card from your graveyard to your hand.
Draw a card.

Shadowspear

Equipped creature gets +1/+1 and has trample and lifelink.
{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.
Equip {2}

Grim Haruspex

Morph {B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
Whenever another nontoken creature you control dies, draw a card.

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Horobi, Death's Wail

Flying
Whenever a creature becomes the target of a spell or ability, destroy that creature.

Midnight Recovery

Return target creature card from your graveyard to your hand.
Cipher (Then you may exile this spell card encoded on a creature you control. Whenever that creature deals combat damage to a player, its controller may cast a copy of the encoded card without paying its mana cost.)

Blood Artist

Whenever this creature or another creature dies, target player loses 1 life and you gain 1 life.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Erratic Portal

{1}, {T}: Return target creature to its owner's hand unless its controller pays {1}.

Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

Morbid Opportunist

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

Grim Tutor

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.