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

Whenever a creature dies, put a charge counter on this enchantment. At the beginning of your first main phase, add {B} for each charge counter on this enchantment.

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.

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.

As this artifact enters, choose a color. Creatures you control of the chosen color get +1/+0. {T}: Add one mana of the chosen color.

Black spells you cast cost {1} less to cast.

{T}: Add one mana of any color. {1}, {T}: Untap target legendary creature you control.

Whenever Ayara or another black creature you control enters, each opponent loses 1 life and you gain 1 life. {T}, Sacrifice another black creature: Draw a card.

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.")

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.

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

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

As this creature enters, choose a creature type. Whenever a creature of the chosen type dies, you may draw a card.

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 artifact enters, choose a creature type. Creatures you control of the chosen type get +1/+1. Whenever you cast a creature spell of the chosen type, draw a card.

Whenever Ashcoat 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.)

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.

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

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."

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

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.

This land enters tapped. When this land enters, exile target player's graveyard. {T}: Add {B}.

{2}, {T}: Add {B} for each Swamp you control.

{T}: Add {C}. {3}, {T}: Add {B} for each basic Swamp you control.

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.

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}: 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.)

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

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.)

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

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.