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

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.)

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.)

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.

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

Charcoal Diamond enters tapped.

{T}: Add {B}.

When Chittering Rats enters, target opponent puts a card from their hand on top of their library.

Corrupted -- Sacrifice an artifact or creature: Draw a card. Activate only if an opponent has three or more poison counters and only once each turn.

When Chittering Witch 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.

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

Sacrifice Commander's Sphere: Draw a card.

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

Draw two cards.

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.

Return target creature card and all other cards with the same name as that card from your graveyard to your hand.

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

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.

Destroy target nonartifact creature.

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.

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.

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.

Ninjutsu {1}{B} ({1}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)

Lifelink

All creatures get -1/-1 until end of turn for each Swamp you control.

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.

Nezumi Bladeblesser has deathtouch as long as you control an artifact.

Nezumi Bladeblesser has menace as long as you control an enchantment. (It can't be blocked except by two or more creatures.)

{B}, Sacrifice a creature: Target player discards a card. Activate only as a sorcery.

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

Nezumi Cutthroat can't block.

{1}{B}: Exile target card from an opponent's graveyard. If no cards are in that graveyard, flip Nezumi Graverobber.

{4}{B}: Put target creature card from a graveyard onto the battlefield under your control.

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

Ninjutsu {1}{B} ({1}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)

When Nezumi Prowler enters, target creature you control gains deathtouch and lifelink until end of turn.

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

Rats you control have deathtouch.

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 Okiba-Gang Shinobi deals combat damage to a player, that player discards two cards.

When Ossuary Rats enters the battlefield, it deals X damage to target creature or planeswalker an opponent controls, where X is the number of creature cards in your graveyard.

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.

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

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.)

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)

Destroy target creature or planeswalker. 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.)

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.

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.

When Ravenous Rats enters the battlefield, target opponent discards a card.

Relentless Rats gets +1/+1 for each other creature on the battlefield named Relentless Rats.

A deck can have any number of cards named Relentless Rats.

When Rotting Rats enters the battlefield, each player discards a card.

Unearth {1}{B} ({1}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Deathtouch

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

{T}: Exile the top card of target player's library. If it's a land card, you gain 1 life.

Landfall -- Whenever a land enters the battlefield under your control, you may untap Scrib Nibblers.

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.

Target player draws two cards and loses 2 life.

{3}{B}{B}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)

As long as Sinuous Vermin is monstrous, it has menace. (It can't be blocked except by two or more creatures.)

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

Whenever Skullsnatcher deals combat damage to a player, exile up to two target cards from that player's graveyard.

{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.

({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}.)

({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.

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)

Equip {1}

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 this Saga enters and after your draw step, add a lore counter.)

I, II -- Each opponent creates a 1/1 black Rat Rogue creature token.

III -- Exile this Saga, then return it to the battlefield transformed under your control.

Flying, haste

When Echo of Death's Wail enters the battlefield, gain control of all Rat tokens.

Whenever Echo of Death's Wail attacks, you may sacrifice another creature. If you do, draw a card.

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

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

Draw two cards.

Trample

When Wave of Rats 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.)