{T}: Add {C}.

{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

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.

When Burglar Rat enters the battlefield, each opponent discards a card.

Changeling (This card is every creature type.)

Changeling Outcast can't block and can't be blocked.

When Chittering Witch enters the battlefield, 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.

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.)

Defender

{T}: Creatures you control gain haste until end of turn.

Choose a creature type. Creatures that aren't of the chosen type get -3/-3 until end of turn.

{X}: Crypt Rats deals X damage to each creature and each player. Spend only black mana on X.

Add {B}{B}{B}.

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

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

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.)

Put any number of target creature cards from your graveyard on top of your library.

Draw a card.

Creatures your opponents control with hexproof can be the targets of spells and abilities you control as though they didn't have hexproof.

{3}, Sacrifice Glaring Spotlight: Creatures you control gain hexproof until end of turn and can't be blocked this turn.

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.

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.

Put a -1/-1 counter on target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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.)

Whenever two or more creatures you control attack a player, look at the top five cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

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.

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

{T}: Add {C}.

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

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)

Other Rats you control have toxic 1.

When Karumonix enters the battlefield, look at the top five cards of your library. You may reveal any number of Rat cards from among them and put the revealed cards into your hand. Put the rest on the bottom of your library in a random order.

Enchant creature or planeswalker you control

When enchanted permanent dies or is put into exile, return that card to the battlefield under your control.

Bushido 1 (Whenever this creature blocks or becomes blocked, it gets +1/+1 until end of turn.)

{1}{B}: Regenerate Kuro's Taken.

When Lord Skitter's Butcher enters the battlefield, choose one --

• Create a 1/1 black Rat creature token with "This creature 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 enters the battlefield under your control, 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 creature can't block."

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.

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)

{T}, Pay 2 life: Add one mana of any color.

Ninjutsu {3}{B} ({3}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)

Whenever Nashi, Moon Sage's Scion deals combat damage to a player, exile the top card of each player's library. Until end of turn, you may play one of those cards. If you cast a spell this way, pay life equal to its mana value rather than paying its mana cost.

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)

Nezumi Cutthroat can't block.

When Nezumi Informant enters the battlefield, each opponent discards a card.

When Nezumi Linkbreaker dies, create a 1/1 red Mercenary creature token with "{T}: Target creature you control gets +1/+0 until end of turn. Activate only as a sorcery."

Sacrifice Nezumi Shadow-Watcher: Destroy target Ninja.

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

Rats you control have deathtouch.

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.

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.)

Pestilence Rats's power is equal to the number of other Rats on the battlefield. (For example, as long as there are two other Rats on the battlefield, Pestilence Rats's power and toughness are 2/3.)

Each opponent gets a poison counter. Then each creature your opponents control gets -1/-1 until end of turn for each poison counter its controller has.

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.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

{T}: Add {C}.

Skulk (This creature can't be blocked by creatures with greater power.)

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

Rat Colony gets +1/+0 for each other Rat you control.

A deck can have any number of cards named Rat Colony.

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)

At the beginning of your upkeep, you may search your library for a Rat card, reveal it, put it into your hand, then shuffle.

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)

Scry 2, then draw two cards. You lose 2 life.

Choose one --

• Return target creature card from your graveyard to your hand.

• Return two target creature cards that share a creature type from your graveyard to your hand.

{T}: Add {C}.

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

Deathtouch

When Ruin Rat dies, exile target card from an opponent's graveyard.

Squad -- Exile four cards from your graveyard. (As an additional cost to cast this spell, you may pay its squad cost any number of times. When this creature enters the battlefield, create that many tokens that are copies of it.)

Menace (This creature can't be blocked except by two or more creatures.)

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Whenever Septic Rats attacks, if defending player is poisoned, it gets +1/+1 until end of turn.

{B}, Pay 1 life: Sewer Rats gets +1/+0 until end of turn. Activate no more than three times each turn.

Target player draws two cards and loses 2 life.

Equipped creature gets +1/-1.

Whenever equipped creature dies, draw two cards.

Equip {1}

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

Shadow (This creature can block or be blocked by only creatures with shadow.)

Whenever Stronghold Rats deals combat damage to a player, each player discards a card.

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control."

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

Swarm of Rats's power is equal to the number of Rats you control.

Target creature gets +1/+0 and gains infect until end of turn. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Tangled Colony can't block.

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

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

Target creature gains undying until end of turn. (When it 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.)

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."

Changeling (This card is every creature type.)

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)

I -- Urza's Saga gains "{T}: Add {C}."

II -- Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"

III -- Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

When Voracious Vermin enters the battlefield, create a 1/1 black Rat creature token with "This creature can't block."

Whenever another creature you control dies, put a +1/+1 counter on Voracious Vermin.

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

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.)

({T}: Add {B}.)

Witch's Cottage enters the battlefield tapped unless you control three or more other Swamps.

When Witch's Cottage enters the battlefield untapped, you may put target creature card from your graveyard on top of your library.