As this enchantment enters, choose a creature type. Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Ward {2} As this creature enters, choose a creature type. This creature is the chosen type in addition to its other types. If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Changeling (This card is every creature type.) As this creature enters, choose a creature type. Whenever another creature you control of the chosen type enters, put a +1/+1 counter on this creature.

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.")

As this enchantment enters, choose a creature type. Whenever a creature you control of the chosen type enters or attacks, draw a card.

This creature can't be blocked. Threshold — Whenever this creature deals combat damage to a player, draw a card. Then discard a card unless seven or more cards are in your graveyard.

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

{T}, Pay 1 life, Sacrifice this land: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

{T}: Add {C}. {U/R}, {T}: Add {U}{U}, {U}{R}, or {R}{R}.

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

{1}, {T}: Add {U}{B}.

{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.

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

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

{1}, {T}: Add {U}{R}.

({T}: Add {U}.)

This land enters tapped unless you have two or more opponents. {T}: Add {B} or {R}.

({T}: Add {R}.)

This land enters 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}, Pay 1 life, Sacrifice this land: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Rivendell enters tapped unless you control a legendary creature. {T}: Add {U}. {1}{U}, {T}: Scry 2. Activate only if you control a legendary creature.

As this land enters, choose a creature type. {T}: Add {C}. {T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.

This land enters tapped unless you control a Swamp. {T}: Add {B}. {B}, {T}: Target creature you control connives X, where X is the number of creatures that died this turn. (Draw X cards, then discard X cards. Put a +1/+1 counter on that creature for each nonland card discarded this way.)

({T}: Add {U} or {R}.) As this land enters, you may pay 2 life. If you don't, it enters tapped.

({T}: Add {U} or {B}.) This land enters tapped unless you control two or more basic lands.

({T}: Add {B}.)

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

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

You have no maximum hand size. {T}: Add one mana of any color.

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

As this artifact enters, choose a creature type. Creatures you control of the chosen type get +1/+1. {T}: Add one mana of any color.

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

{T}: Add {C}. {T}: Add {U} or {B}. This artifact deals 1 damage to you.

{T}: Add {C}. {T}: Add {B} or {R}. This artifact deals 1 damage to you.

Each player chooses a creature type. Each player returns all creature cards of a type chosen this way from their graveyard to the battlefield.

Vigilance This creature can't be blocked by creatures with power 2 or greater. Whenever this creature attacks, up to one target artifact, creature, or planeswalker an opponent controls loses all abilities until your next turn. If it's a creature, it also has base power and toughness 2/2 until your next turn.

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Counter target spell.

Choose a creature type. Destroy all creatures that aren't of the chosen type.

Counter target noncreature spell.

Create two 1/1 green Squirrel creature tokens. Then each creature that isn't an Insect, Rat, Spider, or Squirrel gets -1/-1 until end of turn for each creature you control that's an Insect, Rat, Spider, or Squirrel.

When this creature enters, create a number of 1/1 black Rat creature tokens equal to the number of opponents you have. {1}{B}, Sacrifice a creature: Target creature gets -2/-2 until end of turn.

Creature tokens you control have menace. Whenever you attack a player, choose target nontoken creature that's attacking that player. Create a token that's a copy of that creature, except it's 1/1. The token enters tapped and attacking that player. Sacrifice it at the beginning of the next end step.

When this creature enters, choose one — • Create a 1/1 black Rat creature token with "This token can't block." • You may sacrifice another creature. If you do, scry 2, then draw a card. • Creatures you control gain menace until end of turn.

Whenever another Rat you control enters, exile up to one target card from an opponent's graveyard. At the beginning of combat on your turn, create a 1/1 black Rat creature token with "This token can't block."

Creatures you control are every creature type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield. {3}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

Menace Whenever this creature enters or attacks, create two 1/1 black Rat creature tokens with "This token can't block." Then if you control five or more Rats, each Rat you control gets +2/+0 until end of turn.

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.

Create X 1/1 black Rat creature tokens with "This token can't block." Creatures you control gain haste until end of turn.

Whenever Totentanz or another nontoken creature you control dies, create a 1/1 black Rat creature token with "This token can't block." {1}{B}: Target attacking Rat you control gains deathtouch until end of turn.

When this creature enters, create a 1/1 black Rat creature token with "This token can't block." Whenever another creature you control dies, put a +1/+1 counter on this creature.