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.)

As an additional cost to cast this spell, discard a card or pay 3 life. Destroy target creature or planeswalker.

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

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

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."

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.

As an additional cost to cast this spell, pay X life. All creatures get -X/-X until end of turn.

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.) Each opponent sacrifices a creature of their choice. If you have the city's blessing, instead each opponent sacrifices half the creatures they control of their choice, rounded up.

At the beginning of your first 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.)

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.

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.) Other Rats you control have toxic 1. When Karumonix enters, 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.

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 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.

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.

Choose a creature type. Target player draws X cards and loses X life, where X is the number of creatures they control of the chosen type.

At the beginning of your upkeep, you draw a card and you lose 1 life.

Target player draws two cards and loses 2 life.

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

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.

This creature gets +1/+0 for each other Rat you control. Threshold — Whenever you attack with one or more Rats, if seven or more cards are in your graveyard, you may pay {2}{B}. If you do, return this card from your graveyard to the battlefield tapped and attacking.

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.

As this enchantment enters, choose a creature type. Creatures of the chosen type have fear. (They can't be blocked except by artifact creatures and/or black creatures.)

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.) As long as this card is in your graveyard and you control a Swamp, creatures you control have swampwalk.

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.

As this artifact enters, choose artifact, creature, enchantment, instant, or sorcery. Spells you cast of the chosen type cost {1} less to cast.

Add {B}{B}{B}.

As this artifact enters, choose a creature type. Creature spells you cast of the chosen type cost {1} less to cast. At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Search your library for a card, put that card into your graveyard, then shuffle.

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

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

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

{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.

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

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

{T}: Add {B}. {B}, {T}: Target legendary creature gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)

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 {B}.)

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

{T}: Add {B}. Channel — {3}{B}, Discard this card: Mill three cards, then return a creature or planeswalker card from your graveyard to your hand. This ability costs {1} less to activate for each legendary creature you control.

As The Black Gate enters, you may pay 3 life. If you don't, it enters tapped. {T}: Add {B}. {1}{B}, {T}: Choose a player with the most life or tied for most life. Target creature can't be blocked by creatures that player controls this turn.

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.

Each land is a Swamp in addition to its other land types.

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

Return target creature card from your graveyard to the battlefield. Flashback—Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.