Sacrifice a creature: Add {C}{C}.

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.

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

As Herald's Horn enters the battlefield, 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.

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

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

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

If you would create a Clue, Food, or Treasure token, instead create one of each.

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.)

Whenever you cast a creature spell, draw a card.

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

{1}{B}, Sacrifice an artifact or creature: Draw a card.

Flying When Gilded Goose enters the battlefield, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.") {1}{G}, {T}: Create a Food token. {T}, Sacrifice a Food: Add one mana of any color.

Each opponent's maximum hand size is reduced by one.

Ninjutsu {3}{B}{B} ({3}{B}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.) Whenever Ink-Eyes, Servant of Oni deals combat damage to a player, you may put target creature card from that player's graveyard onto the battlefield under your control. {1}{B}: Regenerate Ink-Eyes.

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 {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.

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.

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.

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.

Whenever a player casts a creature spell, each player returns all cards with the same name as that spell from their graveyard to the battlefield.

Creatures you control have "{T}: Add one mana of any color."

Sacrifice a creature: Draw cards equal to the sacrificed creature's power, then discard three cards.

When Killer Service enters the battlefield, create a number of Food tokens equal to the number of opponents you have. (They're artifacts with "{2}, {T}, Sacrifice this artifact: You gain 3 life.") At the beginning of your end step, you may pay {2} and sacrifice a token. If you do, create a 4/4 green Rhino Warrior creature token.

Commander creatures you own have "This creature enters the battlefield with an additional +1/+1 counter on it" and "Other creatures you control enter the battlefield with an additional +1/+1 counter on them."

Bojuka Bog enters the battlefield tapped. When Bojuka Bog enters the battlefield, exile target player's graveyard. {T}: Add {B}.

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

Crypt of Agadeem enters the battlefield tapped. {T}: Add {B}. {2}, {T}: Add {B} for each black creature card in your graveyard.

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

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

({T}: Add {G}.)

Golgari Rot Farm enters the battlefield tapped. When Golgari Rot Farm enters the battlefield, return a land you control to its owner's hand. {T}: Add {B}{G}.

{T}: Add {C}. {T}, Sacrifice a creature: You gain 1 life.

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

{T}: Add {C}. {T}, Sacrifice a creature: Add {B}{B}.

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

({T}: Add {B}.)

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

Temple of Malady enters the battlefield tapped. When Temple of Malady enters the battlefield, scry 1. {T}: Add {B} or {G}.

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

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

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

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Until end of turn, creatures you control gain trample and get +X/+X, where X is the greatest power among creatures you control.

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Sacrifice any number of artifacts, creatures, and/or lands. Draw a card for each permanent sacrificed this way.

Exile target nonland card from your graveyard. Search your library for any number of cards with the same name as that card, reveal them, put them into your hand, then shuffle.