Swamp

Contamination

At the beginning of your upkeep, sacrifice Contamination unless you sacrifice a creature.
If a land is tapped for mana, it produces {B} instead of any other type and amount.

Cackling Fiend

When Cackling Fiend enters, each opponent discards a card.

Noosegraf Mob

Noosegraf Mob enters with five +1/+1 counters on it.
Whenever a player casts a spell, remove a +1/+1 counter from Noosegraf Mob. If you do, create a 2/2 black Zombie creature token.

Bitterthorn, Nissa's Animus

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/+1.
Whenever equipped creature attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Equip {3}

Temple of the Dead

(Transforms from Aclazotz, Deepest Betrayal.)
{T}: Add {B}.
{2}{B}, {T}: Transform Temple of the Dead. Activate only if a player has one or fewer cards in hand and only as a sorcery.

Aclazotz, Deepest Betrayal

Flying, lifelink
Whenever Aclazotz attacks, each opponent discards a card. For each opponent who can't, you draw a card.
Whenever an opponent discards a land card, create a 1/1 black Bat creature token with flying.
When Aclazotz dies, return it to the battlefield tapped and transformed under its owner's control.

Aclazotz, Deepest Betrayal // Temple of the Dead

Criminal Past

Commander creatures you own have menace and "This creature gets +X/+0, where X is the number of creature cards in your graveyard." (A creature with menace can't be blocked except by two or more creatures.)

Insatiable Avarice

Spree (Choose one or more additional costs.)
+ {2} — Search your library for a card, then shuffle and put that card on top.
+ {B}{B} — Target player draws three cards and loses 3 life.

Plague Spitter

At the beginning of your upkeep, Plague Spitter deals 1 damage to each creature and each player.
When Plague Spitter dies, it deals 1 damage to each creature and each player.

Spread the Sickness

Destroy target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Destroy target creature.

Bitter Downfall

This spell costs {3} less to cast if it targets a creature that was dealt damage this turn.
Destroy target creature. Its controller loses 2 life.

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Contagion Clasp

When Contagion Clasp enters, put a -1/-1 counter on target creature.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Crippling Fear

Choose a creature type. Creatures that aren't of the chosen type get -3/-3 until end of turn.

Befoul

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

Diseased Vermin

Whenever Diseased Vermin deals combat damage to a player, put an infection counter on it.
At the beginning of your upkeep, Diseased Vermin deals X damage to target opponent previously dealt damage by it, where X is the number of infection counters on it.

Virus Beetle

When Virus Beetle enters, each opponent discards a card.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Sol Ring

Dementia Bat

Flying
{4}{B}, Sacrifice Dementia Bat: Target player discards two cards.

Cast Down

Maga, Traitor to Mortals

Maga, Traitor to Mortals enters with X +1/+1 counters on it.
When Maga enters, target player loses life equal to the number of +1/+1 counters on it.

Bankrupt in Blood

As an additional cost to cast this spell, sacrifice two creatures.
Draw three cards.

Debtors' Transport

Afterlife 2 (When this creature dies, create two 1/1 white and black Spirit creature tokens with flying.)

Brink of Disaster

Enchant creature or land
When enchanted permanent becomes tapped, destroy it.

Greed

Breathe Your Last

Destroy target creature or planeswalker. You gain 1 life for each of its colors.

Heartless Act

Choose one —
• Destroy target creature with no counters on it.
• Remove up to three counters from target creature.

Golden Demise

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
All creatures get -2/-2 until end of turn. If you have the city's blessing, instead only creatures your opponents control get -2/-2 until end of turn.

Ambition's Cost

You draw three cards and you lose 3 life.

Repeat Offender

{2}{B}: If Repeat Offender is suspected, put a +1/+1 counter on it. Otherwise, suspect it. (A suspected creature has menace and can't block.)

Suffocating Fumes

Creatures your opponents control get -1/-1 until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Hatred

As an additional cost to cast this spell, pay X life.
Target creature gets +X/+0 until end of turn.

Black Market Connections

At the beginning of your first main phase, choose one or more —
• Sell Contraband — Create a Treasure token. You lose 1 life.
• Buy Information — Draw a card. You lose 2 life.
• Hire a Mercenary — Create a 3/2 colorless Shapeshifter creature token with changeling. You lose 3 life. (It has every creature type.)

Gibbering Barricade

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

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Promise of Power

Choose one —
• You draw five cards and you lose 5 life.
• Create an X/X black Demon creature token with flying, where X is the number of cards in your hand.
Entwine {4} (Choose both if you pay the entwine cost.)

Sick and Tired

Two target creatures each get -1/-1 until end of turn.

Plaguebearer

{X}{X}{B}: Destroy target nonblack creature with mana value X.

Trading Post

{1}, {T}, Discard a card: You gain 4 life.
{1}, {T}, Pay 1 life: Create a 0/1 white Goat creature token.
{1}, {T}, Sacrifice a creature: Return target artifact card from your graveyard to your hand.
{1}, {T}, Sacrifice an artifact: Draw a card.

Darkness

Prevent all combat damage that would be dealt this turn.

Staff of Compleation

{T}, Pay 1 life: Destroy target permanent you own.
{T}, Pay 2 life: Add one mana of any color.
{T}, Pay 3 life: Proliferate.
{T}, Pay 4 life: Draw a card.
{5}: Untap Staff of Compleation.

Corrupt Official

{2}{B}: Regenerate Corrupt Official.
Whenever Corrupt Official becomes blocked, defending player discards a card at random.

Traitor's Clutch

Target creature gets +1/+0, becomes black, and gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)
Flashback {1}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Oppression

Whenever a player casts a spell, that player discards a card.

Archfiend of Spite

Flying
Whenever a source an opponent controls deals damage to Archfiend of Spite, that source's controller loses that much life unless they sacrifice that many permanents of their choice.
Madness {3}{B}{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.)

Corrupt

Corrupt deals damage to any target equal to the number of Swamps you control. You gain life equal to the damage dealt this way.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Wall of Putrid Flesh

Defender (This creature can't attack.)
Protection from white
Prevent all damage that would be dealt to Wall of Putrid Flesh by enchanted creatures.

Arcane Signet

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

Bad Deal

You draw two cards and each opponent discards two cards. Each player loses 2 life.

Plaguecrafter

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

Dark Betrayal

Crushing Disappointment

Each player loses 2 life. You draw two cards.

Liar's Pendulum

{2}, {T}: Choose a card name. Target opponent guesses whether a card with that name is in your hand. You may reveal your hand. If you do and your opponent guessed wrong, draw a card.

Contagion Engine

When Contagion Engine enters, put a -1/-1 counter on each creature target player controls.
{4}, {T}: Proliferate twice. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

Charcoal Diamond

Charcoal Diamond enters tapped.
{T}: Add {B}.

Disease Carriers

When Disease Carriers dies, target creature gets -2/-2 until end of turn.

Archfiend of Depravity

Flying
At the beginning of each opponent's end step, that player chooses up to two creatures they control, then sacrifices the rest.

Consuming Corruption

Consuming Corruption deals X damage to target creature or planeswalker and you gain X life, where X is the number of Swamps you control.

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.

Revel in Riches

Whenever a creature an opponent controls dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
At the beginning of your upkeep, if you control ten or more Treasures, you win the game.

Spoils of Evil

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

Suppress

Target player exiles all cards from their hand face down. At the beginning of the end step of that player's next turn, that player returns those cards to their hand.

Cruel Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Grim Hireling

Whenever one or more creatures you control deal combat damage to a player, create two Treasure tokens.
{B}, Sacrifice X Treasures: Target creature gets -X/-X until end of turn. Activate only as a sorcery.