Choose odd or even. Exile each creature with mana value of the chosen quality. (Zero is even.)

Karn's Sylex enters the battlefield tapped. Players can't pay life to cast spells or to activate abilities that aren't mana abilities. {X}, {T}, Exile Karn's Sylex: Destroy each nonland permanent with mana value X or less. Activate only as a sorcery.

All creatures get -4/-4 until end of turn.

Each player exiles all creature cards from their graveyard, then sacrifices all creatures they control, then puts all cards they exiled this way onto the battlefield.

At the beginning of your precombat 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.)

You may look at the top card of your library any time. You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost. {T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

Whenever a creature deals combat damage to one of your opponents, its controller may pay 1 life. If they do, they draw a card. {4}{B}{B}{B}, Discard X cards: Exile the top X cards of target opponent's library. You may play lands and cast spells from among cards exiled this way without paying their mana costs.

You draw two cards and you lose 2 life. Each opponent gets a poison counter.

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.

You draw two cards and you lose 2 life.

Equipped creature gets +1/-1. Whenever equipped creature dies, draw two cards. Equip {1}

Barren Moor enters the battlefield tapped. {T}: Add {B}. Cycling {B} ({B}, Discard this card: Draw a card.)

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

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

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

Castle Locthwain enters the battlefield tapped unless you control a Swamp. {T}: Add {B}. {1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.

{T}: Add {C}. {4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Myriad Landscape enters the battlefield tapped. {T}: Add {C}. {2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

{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.)

Path of Ancestry enters the battlefield tapped. {T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

({T}: Add {B}.)

{T}: Add {C}. {T}: Regenerate target Insect, Rat, Spider, or Squirrel. (The next time it would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)

Whenever Ashcoat of the Shadow Swarm attacks or blocks, other Rats you control get +X/+X until end of turn, where X is the number of Rats you control. At the beginning of your end step, you may mill four cards. If you do, return up to two Rat creature cards from your graveyard to your hand. (To mill a card, put the top card of your library into your graveyard.)

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

When Contagion Clasp enters the battlefield, 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.)

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

As Door of Destinies enters the battlefield, choose a creature type. Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies. Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

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

Rats you control have menace. {1}{B}, {T}: Create a 1/1 black Rat creature token. {2}{B}{B}, {T}, Sacrifice three Rats: Gain control of target creature.

Rat Colony gets +1/+0 for each other Rat you control. A deck can have any number of cards named Rat Colony.

{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.

Spells you cast have ripple 4. (Whenever you cast a spell, you may reveal the top four cards of your library. You may cast spells with the same name as that spell from among the revealed cards without paying their mana costs. Put the rest on the bottom of your library.)

As Vanquisher's Banner enters the battlefield, choose a creature type. Creatures you control of the chosen type get +1/+1. Whenever you cast a creature spell of the chosen type, draw a card.

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

Add {B}{B}{B}.

{T}: Add one mana of any color that a land an opponent controls could produce.

Glistening Sphere enters the battlefield tapped. When Glistening Sphere enters the battlefield, proliferate. {T}: Add one mana of any color. Corrupted — {T}: Add three mana of any one color. Activate only if an opponent has three or more poison counters.

As Heraldic Banner enters the battlefield, choose a color. Creatures you control of the chosen color get +1/+0. {T}: Add one mana of the chosen color.

{T}: Add {C}. {1}, {T}, Sacrifice Mind Stone: Draw a card.

Nyx Lotus enters the battlefield 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.)

{T}: Add {C}{C}.

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

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

{T}: Add {C}{C}{C}.

Kicker {2}{B} (You may pay an additional {2}{B} as you cast this spell.) Destroy target creature or planeswalker with mana value 2 or less. If this spell was kicked, instead destroy target creature or planeswalker.

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

Target creature gets -4/-4 until end of turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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

Destroy target creature. You lose 2 life.

Whenever a creature you control dies, draw a card. +1: Create a 2/2 black Zombie creature token. −4: Each player sacrifices two creatures. −9: Each opponent chooses a permanent they control of each permanent type and sacrifices the rest.

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost. Destroy target nonblack creature. It can't be regenerated.

Target creature gets -1/-1 until end of turn. Morbid — That creature gets -13/-13 until end of turn instead if a creature died this turn.

Each opponent sacrifices a creature or planeswalker and gets a poison counter.

Black creatures get +1/+1.

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.) When Blightbelly Rat dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Bog Rats can't be blocked by Walls.

Black creature spells you cast cost {1} less to cast. Whenever you cast a creature spell, each opponent loses 1 life and you gain 1 life.

Target player draws three cards, loses 3 life, and gets three poison counters.

Changeling (This card is every creature type.) Changeling Outcast can't block and can't be blocked.

When Drainpipe Vermin dies, you may pay {B}. If you do, target player discards a card.

Each opponent's maximum hand size is reduced by one.

When Gnawing Vermin enters the battlefield, target player mills two cards. When Gnawing Vermin dies, target creature you don't control gets -1/-1 until end of turn.

{B}, Pay 2 life: Draw a card.

Commander creatures you own have "Whenever this creature becomes tapped, it and other creatures you control that share a creature type with it each get +2/+0 and gain undying until end of turn." (When a creature with undying 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.)

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) When Ichor Rats enters the battlefield, each player gets a poison counter.

All Rats have fear. {T}, Sacrifice a Rat: Create X 1/1 black Rat creature tokens, where X is the number of Rats you control.

Pack Rat's power and toughness are each equal to the number of Rats you control. {2}{B}, Discard a card: Create a token that's a copy of Pack Rat.

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

Starting with you, each player may pay any amount of life. Repeat this process until no one pays life. Each player creates a 1/1 black Rat creature token for each 1 life they paid this way.

Target player draws two cards and loses 2 life.

Equipped creature gets +2/+2 and has protection from white and from blue. Whenever equipped creature deals combat damage to a player, put a +1/+1 counter on a creature you control, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.) Equip {2}

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Target creature gets -1/-1 until end of turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)