Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Darksteel Plate

Indestructible
Equipped creature has indestructible.
Equip {2}

Cloak and Dagger

Equipped creature gets +2/+0 and has shroud. (It can't be the target of spells or abilities.)
Whenever a Rogue creature enters, you may attach this Equipment to it.
Equip {3}

Torpor Orb

Creatures entering don't cause abilities to trigger.

Infernal Grasp

Destroy target creature. You lose 2 life.

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Toxic Deluge

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

Teferi's Puzzle Box

At the beginning of each player's draw step, that player puts the cards in their hand on the bottom of their library in any order, then draws that many cards.

Fell Mire

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}.

Fell the Profane

Fell the Profane // Fell Mire

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Exquisite Blood

Whenever an opponent loses life, you gain that much life.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Throne of Eldraine

As Throne of Eldraine enters, choose a color.
{T}: Add four mana of the chosen color. Spend this mana only to cast monocolored spells of that color.
{3}, {T}: Draw two cards. Spend only mana of the chosen color to activate this ability.

Command Tower

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

Feign Death

Until end of turn, target creature gains "When this creature dies, return it to the battlefield tapped under its owner's control with a +1/+1 counter on it."

Sol Ring

Offer Immortality

Target creature gains deathtouch and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Commander's Sphere

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

Swamp

Demolition Field

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Destroy target nonbasic land an opponent controls. That land's controller may search their library for a basic land card, put it onto the battlefield, then shuffle. You may search your library for a basic land card, put it onto the battlefield, then shuffle.

Damnation

Destroy all creatures. They can't be regenerated.

Trinisphere

As long as this artifact is untapped, each spell that would cost less than three mana to cast costs three mana to cast. (Additional mana in the cost may be paid with any color of mana or colorless mana. For example, a spell that would cost {1}{B} to cast costs {2}{B} to cast instead.)

Jet Medallion

Black spells you cast cost {1} less to cast.

Defense Grid

Each spell costs {3} more to cast except during its controller's turn.

Cabal Ritual

Add {B}{B}{B}.
Threshold — Add {B}{B}{B}{B}{B} instead if seven or more cards are in your graveyard.

Rankle's Prank

Choose one or more —
• Each player discards two cards.
• Each player loses 4 life.
• Each player sacrifices two creatures of their choice.

Bojuka Bog

This land enters tapped.
When this land enters, exile target player's graveyard.
{T}: Add {B}.

Takenuma, Abandoned Mire

{T}: Add {B}.
Channel — {3}{B}, Discard this card: Mill three cards, then return a creature or planeswalker card from your graveyard to your hand. This ability costs {1} less to activate for each legendary creature you control.

Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Unearth

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Terramorphic Expanse

Armor of Shadows

Until end of turn, target creature gets +1/+0 and gains indestructible. (Damage and effects that say "destroy" don't destroy it.)

Ob Nixilis, Unshackled

Flying, trample
Whenever an opponent searches their library, that player sacrifices a creature of their choice and loses 10 life.
Whenever another creature dies, put a +1/+1 counter on Ob Nixilis.

Arcane Signet

Mutilate

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

Platinum Angel

Flying
You can't lose the game and your opponents can't win the game.

Cabal Stronghold

{T}: Add {C}.
{3}, {T}: Add {B} for each basic Swamp you control.

Dark Deal

Each player discards all the cards in their hand, then draws that many cards minus one.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Abyssal Persecutor

Flying, trample
You can't win the game and your opponents can't lose the game.

Dread Return

Return target creature card from your graveyard to the battlefield.
Flashback—Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Witch's Cottage

({T}: Add {B}.)
This land enters tapped unless you control three or more other Swamps.
When this land enters untapped, you may put target creature card from your graveyard on top of your library.

Bubbling Muck

Until end of turn, whenever a player taps a Swamp for mana, that player adds an additional {B}.

Feed the Swarm

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

Meekstone

Creatures with power 3 or greater don't untap during their controllers' untap steps.

Imp's Mischief

Change the target of target spell with a single target. You lose life equal to that spell's mana value.

Strip Mine

{T}: Add {C}.
{T}, Sacrifice this land: Destroy target land.

Hero's Downfall

Reliquary Tower

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

Jeweled Lotus

{T}, Sacrifice this artifact: Add three mana of any one color. Spend this mana only to cast your commander.

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}.

Go for the Throat

Ulamog, the Ceaseless Hunger

When you cast this spell, exile two target permanents.
Indestructible
Whenever Ulamog attacks, defending player exiles the top twenty cards of their library.

Dark Ritual

Stitch Together

Return target creature card from your graveyard to your hand.
Threshold — Return that card from your graveyard to the battlefield instead if seven or more cards are in your graveyard.

Doom Blade

Baleful Mastery

You may pay {1}{B} rather than pay this spell's mana cost.
If the {1}{B} cost was paid, an opponent draws a card.
Exile target creature or planeswalker.

Maralen of the Mornsong

Players can't draw cards.
At the beginning of each player's draw step, that player loses 3 life, searches their library for a card, puts it into their hand, then shuffles.

Thought Vessel

Bitter Triumph

As an additional cost to cast this spell, discard a card or pay 3 life.
Destroy target creature or planeswalker.

Winter Orb

As long as this artifact is untapped, players can't untap more than one land during their untap steps.

Void Winnower

Your opponents can't cast spells with even mana values. (Zero is even.)
Your opponents can't block with creatures with even mana values.

Mithril Coat

Flash
Indestructible
When Mithril Coat enters, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip {3}

Cut Down

Destroy target creature with total power and toughness 5 or less.

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.)

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

Elder Brain

Menace
Whenever this creature attacks a player, exile all cards from that player's hand, then they draw that many cards. You may play lands and cast spells from among the exiled cards for as long as they remain exiled. If you cast a spell this way, you may spend mana as though it were mana of any color to cast it.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Possessed Portal

If a player would draw a card, that player skips that draw instead.
At the beginning of each end step, each player sacrifices a permanent of their choice unless they discard a card.

Cursed Totem

Activated abilities of creatures can't be activated.

Mindcrank

Whenever an opponent loses life, that player mills that many cards. (Damage causes loss of life.)

Cabal Coffers

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

Deadly Rollick

If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Choice of Damnations

Target opponent chooses a number. You may have that player lose that much life. If you don't, that player sacrifices all but that many permanents of their choice.

Gravedigger

When this creature enters, you may return target creature card from your graveyard to your hand.