Lilypad Village

{T}: Add {C}.
{T}: Add {U}. Spend this mana only to cast a creature spell.
{U}, {T}: Surveil 2. Activate only if a Bird, Frog, Otter, or Rat entered the battlefield under your control this turn.

Marrow-Gnawer

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.

Wick, the Whorled Mind

Whenever Wick or another Rat you control enters, create a 1/1 black Snail creature token if you don't control a Snail. Otherwise, put a +1/+1 counter on a Snail you control.
{U}{B}{R}, Sacrifice a Snail: Wick deals damage equal to the sacrificed creature's power to each opponent. Then draw cards equal to the sacrificed creature's power.

Rat Colony

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

Mockingbird

Flying
You may have this creature enter as a copy of any creature on the battlefield with mana value less than or equal to the amount of mana spent to cast this creature, except it's a Bird in addition to its other types and it has flying.

Taurean Mauler

Changeling (This card is every creature type.)
Whenever an opponent casts a spell, you may put a +1/+1 counter on this creature.

Revenge of the Rats

Create a tapped 1/1 black Rat creature token for each creature card in your graveyard.
Flashback {2}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Darkwater Catacombs

Vivid Creek

This land enters tapped with two charge counters on it.
{T}: Add {U}.
{T}, Remove a charge counter from this land: Add one mana of any color.

Splash Portal

Exile target creature you control, then return it to the battlefield under its owner's control. If that creature is a Bird, Frog, Otter, or Rat, draw a card.

Temple of Malice

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {B} or {R}.

Brainsurge

Draw four cards, then put two cards from your hand on top of your library in any order.

Moonglove Changeling

Changeling (This card is every creature type.)
{B}: This creature gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy that creature.)

Smoldering Marsh

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

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Burglar Rat

When this creature enters, each opponent discards a card.

Command Tower

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

Crumbling Necropolis

This land enters tapped.
{T}: Add {U}, {B}, or {R}.

Rat in the Hat

{T}, Sacrifice this creature: Until end of turn, you may cast target creature card that has a hat from your graveyard.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Gnawing Crescendo

Creatures you control get +2/+0 until end of turn. Whenever a nontoken creature you control dies this turn, create a 1/1 black Rat creature token with "This token can't block."

Triskaidekaphile

You have no maximum hand size.
At the beginning of your upkeep, if you have exactly thirteen cards in your hand, you win the game.
{3}{U}: Draw a card.

Stargaze

Look at twice X cards from the top of your library. Put X cards from among them into your hand and the rest into your graveyard. You lose X life.

Bloodline Pretender

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.

Vren, the Relentless

Ward {2}
If a creature an opponent controls would die, exile it instead.
At the beginning of each end step, create X 1/1 black Rat creature tokens with "This token gets +1/+1 for each other Rat you control," where X is the number of creatures that were exiled under your opponents' control this turn.

Skullcap Snail

When this creature enters, target opponent exiles a card from their hand.

Wave of Rats

Trample
When this creature dies, if it dealt combat damage to a player this turn, return it to the battlefield under its owner's control.
Blitz {4}{B} (If you cast this spell for its blitz cost, it gains haste and "When this creature dies, draw a card." Sacrifice it at the beginning of the next end step.)

Diresight

Surveil 2, then draw two cards. You lose 2 life. (To surveil 2, look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Rat Out

Up to one target creature gets -1/-1 until end of turn. You create a 1/1 black Rat creature token with "This token can't block."

Chaos Warp

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.

Amoeboid Changeling

Changeling (This card is every creature type.)
{T}: Target creature gains all creature types until end of turn.
{T}: Target creature loses all creature types until end of turn.

Changeling Outcast

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

Commander's Sphere

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

Secluded Glen

As this land enters, you may reveal a Faerie card from your hand. If you don't, this land enters tapped.
{T}: Add {U} or {B}.

Plague of Vermin

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.

Arcane Signet

Swamp

Myriad Landscape

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

Pack Rat

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 this creature.

Song of Totentanz

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

Maskwood Nexus

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.)

Auntie's Hovel

As this land enters, you may reveal a Goblin card from your hand. If you don't, this land enters tapped.
{T}: Add {B} or {R}.

Fellwar Stone

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

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Infernal Grasp

Destroy target creature. You lose 2 life.

Mountain

Swarmyard Massacre

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.

Sol Ring

Dimir Aqueduct

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {U}{B}.

Barkform Harvester

Changeling (This card is every creature type.)
Reach
{2}: Put target card from your graveyard on the bottom of your library.

Patriarch's Bidding

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

Getting

Dark Ritual

Voracious Vermin

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.

Tangled Colony

This creature can't block.
When this creature dies, create X 1/1 black Rat creature tokens with "This token can't block," where X is the amount of damage dealt to it this turn.

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Exotic Orchard

Barren Moor

This land enters tapped.
{T}: Add {B}.
Cycling {B} ({B}, Discard this card: Draw a card.)

Piper of the Swarm

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.

Island

Thought Vessel

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

Chittering Witch

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.

Sunken Ruins

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

Leyline of Transformation

If this card is in your opening hand, you may begin the game with it on the battlefield.
As this enchantment enters, choose a creature type.
Creatures you control are the chosen type in addition to their other types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

Three Tree City

As Three Tree City enters, choose a creature type.
{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to the number of creatures you control of the chosen type.

Changeling Berserker

Changeling (This card is every creature type.)
Haste
Champion a creature (When this enters, sacrifice it unless you exile another creature you control. When this leaves the battlefield, that card returns to the battlefield.)

Hidden Grotto

When this land enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Feed the Swarm

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

Totentanz, Swarm Piper

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.

Spellgyre

Choose one —
• Counter target spell.
• Surveil 2, then draw two cards. (To surveil 2, look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Drainpipe Vermin

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

Unleash Fury

Double the power of target creature until end of turn.

Three Tree Mascot

Changeling (This card is every creature type.)
{1}: Add one mana of any color. Activate only once each turn.

Evolving Wilds

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

Cascade Bluffs

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

Innocuous Rat

When this creature dies, manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

Daggerfang Duo

Deathtouch
When this creature enters, you may mill two cards. (You may put the top two cards of your library into your graveyard.)

Mothdust Changeling

Changeling (This card is every creature type.)
Tap an untapped creature you control: This creature gains flying until end of turn.

Sunken Hollow

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

Mudflat Village

{T}: Add {C}.
{T}: Add {B}. Spend this mana only to cast a creature spell.
{1}{B}, {T}, Sacrifice this land: Return target Bat, Lizard, Rat, or Squirrel card from your graveyard to your hand.

Lord Skitter's Butcher

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.

Shore Up

Target creature you control gets +1/+1 and gains hexproof until end of turn. Untap it. (It can't be the target of spells or abilities your opponents control.)

Reliquary Tower

Shipwreck Marsh

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

Lightning Greaves

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

Long River's Pull

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Counter target creature spell. If the gift was promised, instead counter target spell.

Thriving Moor

This land enters tapped. As it enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Lord Skitter, Sewer King

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."

Decanter of Endless Water

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

Path of Ancestry

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.)

Thornplate Intimidator

Offspring {3} (You may pay an additional {3} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
When this creature enters, target opponent loses 3 life unless they sacrifice a nonland permanent of their choice or discard a card.

Pest Problem

Create two 1/1 black Rat creature tokens with "This token can't block." (Then exile this card. You may cast the creature later from exile.)