Sudden Spoiling

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Until end of turn, creatures target player controls lose all abilities and have base power and toughness 0/2.

Swift End

Destroy target creature or planeswalker. You lose 2 life. (Then exile this card. You may cast the creature later from exile.)

Murderous Rider

Lifelink
When Murderous Rider dies, put it on the bottom of its owner's library.

Murderous Rider // Swift End

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Varragoth, Bloodsky Sire

Deathtouch
Boast — {1}{B}: Target player searches their library for a card, then shuffles and puts that card on top. (Activate only if this creature attacked this turn and only once each turn.)

Profane Transfusion

Two target players exchange life totals. You create an X/X colorless Horror artifact creature token, where X is the difference between those players' life totals.

Rogue's Passage

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

Feed the Swarm

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

Burnished Hart

{3}, Sacrifice this creature: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Campfire

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

Dark Ritual

Darkness

Prevent all combat damage that would be dealt this turn.

Sol Ring

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.)

Dauthi Embrace

{B}{B}: Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)

Commander's Plate

Equipped creature gets +3/+3 and has protection from each color that's not in your commander's color identity.
Equip commander {3}
Equip {5}

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}.

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.)

Sengir, the Dark Baron

Flying
Whenever another creature dies, put two +1/+1 counters on Sengir, the Dark Baron.
Whenever another player loses the game, you gain life equal to that player's life total as the turn began.
Partner (You can have two commanders if both have partner.)

Profane Tutor

Suspend 2—{1}{B} (Rather than cast this card from your hand, pay {1}{B} and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Search your library for a card, put that card into your hand, then shuffle.

Black Market

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

Geode Golem

Trample
Whenever Geode Golem deals combat damage to a player, you may cast your commander from the command zone without paying its mana cost. (You still pay any additional costs.)

Magus of the Coffers

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

Reliquary Tower

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

Toxic Deluge

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

Phyrexian Obliterator

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

Vampiric Tutor

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

No Mercy

Whenever a creature deals damage to you, destroy it.

Dread Presence

Whenever a Swamp you control enters, choose one —
• You draw a card and you lose 1 life.
• Dread Presence deals 2 damage to any target and you gain 2 life.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {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.)

Lightning Greaves

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

Greed

Endless Whispers

Each creature has "When this creature dies, choose target opponent. That player puts this card from its owner's graveyard onto the battlefield under their control at the beginning of the next end step."

Grave Betrayal

Whenever a creature you don't control dies, return it to the battlefield under your control with an additional +1/+1 counter on it at the beginning of the next end step. That creature is a black Zombie in addition to its other colors and types.

Exsanguinate

Each opponent loses X life. You gain life equal to the life lost this way.

Command Beacon

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

Vesuva

You may have Vesuva enter tapped as a copy of any land on the battlefield.

Cabal Coffers

Expedition Map

{2}, {T}, Sacrifice this artifact: Search your library for a land card, reveal it, put it into your hand, then shuffle.

Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent of their choice or discards a card.

Withering Boon

As an additional cost to cast this spell, pay 3 life.
Counter target creature spell.

Imp's Mischief

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

Platinum Angel

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

Key to the City

{T}, Discard a card: Up to one target creature can't be blocked this turn.
Whenever Key to the City becomes untapped, you may pay {2}. If you do, draw a card.

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.)

Rune-Scarred Demon

Flying
When this creature enters, search your library for a card, put it into your hand, then shuffle.

Cabal Stronghold

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

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.

Stinging Study

You draw X cards and you lose X life, where X is the mana value of a commander you own on the battlefield or in the command zone.

Dauthi Voidwalker

Shadow (This creature can block or be blocked by only creatures with shadow.)
If a card would be put into an opponent's graveyard from anywhere, instead exile it with a void counter on it.
{T}, Sacrifice Dauthi Voidwalker: Choose an exiled card an opponent owns with a void counter on it. You may play it this turn without paying its mana cost.

Sundial of the Infinite

{1}, {T}: End the turn. Activate only during your turn. (Exile all spells and abilities from the stack. Discard down to your maximum hand size. Damage wears off, and "this turn" and "until end of turn" effects end.)

Dark Petition

Search your library for a card, put that card into your hand, then shuffle.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, add {B}{B}{B}.

Burning-Rune Demon

Flying
When Burning-Rune Demon enters, you may search your library for exactly two cards not named Burning-Rune Demon that have different names. If you do, reveal those cards. An opponent chooses one of them. Put the chosen card into your hand and the other into your graveyard, then shuffle.

Phage the Untouchable

When Phage the Untouchable enters, if you didn't cast it from your hand, you lose the game.
Whenever Phage deals combat damage to a creature, destroy that creature. It can't be regenerated.
Whenever Phage deals combat damage to a player, that player loses the game.

Extraplanar Lens

Imprint — When Extraplanar Lens enters, you may exile target land you control.
Whenever a land with the same name as the exiled card is tapped for mana, its controller adds one mana of any type that land produced.

Demonic Tutor

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

Defile

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

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.

Twilight Prophet

Flying
Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
At the beginning of your upkeep, if you have the city's blessing, reveal the top card of your library and put it into your hand. Each opponent loses X life and you gain X life, where X is that card's mana value.

Nirkana Revenant

Whenever you tap a Swamp for mana, add an additional {B}.
{B}: Nirkana Revenant gets +1/+1 until end of turn.

Stunning Reversal

The next time you would lose the game this turn, instead draw seven cards and your life total becomes 1.
Exile Stunning Reversal.

Filth

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
As long as Filth is in your graveyard and you control a Swamp, creatures you control have swampwalk.

Dream Devourer

Each nonland card in your hand without foretell has foretell. Its foretell cost is equal to its mana cost reduced by {2}. (During your turn, you may pay {2} and exile it from your hand face down. Cast it on a later turn for its foretell cost.)
Whenever you foretell a card, Dream Devourer gets +2/+0 until end of turn.

Beseech the Queen

({2/B} can be paid with any two mana or with {B}. This card's mana value is 6.)
Search your library for a card with mana value less than or equal to the number of lands you control, reveal it, put it into your hand, then shuffle.

Vampire Nighthawk

Flying
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Liliana of the Dark Realms

+1: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.
−3: Target creature gets +X/+X or -X/-X until end of turn, where X is the number of Swamps you control.
−6: You get an emblem with "Swamps you control have '{T}: Add {B}{B}{B}{B}.'"

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.

Grim Tutor

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

Sidisi, Undead Vizier

Deathtouch
Exploit (When this creature enters, you may sacrifice a creature.)
When Sidisi, Undead Vizier exploits a creature, you may search your library for a card, put it into your hand, then shuffle.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Phyrexian Reclamation

{1}{B}, Pay 2 life: Return target creature card from your graveyard to your hand.

Snow-Covered Swamp

Urborg, Tomb of Yawgmoth

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

Netherborn Altar

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