As Adaptive Automaton enters the battlefield, choose a creature type.

Adaptive Automaton is the chosen type in addition to its other types.

Other creatures you control of the chosen type get +1/+1.

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

Whenever Ayara, First of Locthwain or another black creature enters the battlefield under your control, each opponent loses 1 life and you gain 1 life.

{T}, Sacrifice another black creature: Draw a card.

({2/B} can be paid with any two mana or with {B}. This card's mana value is 6.)

Search your library for a card with mana value less than or equal to the number of lands you control, reveal it, put it into your hand, then shuffle.

Whenever a creature dies, put a charge counter on Black Market.

At the beginning of your precombat main phase, add {B} for each charge counter on Black Market.

Put X -1/-1 counters on each creature. Shuffle Black Sun's Zenith into its owner's library.

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Flying

Echo {2}{B} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)

When Bone Shredder enters the battlefield, destroy target nonartifact, nonblack creature.

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.

{T}: Add {C}.

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

Charcoal Diamond enters the battlefield tapped.

{T}: Add {B}.

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.

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.)

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Whenever you tap a Swamp for mana, add an additional {B}.

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

Destroy all creatures. They can't be regenerated.

Add {B}{B}{B}.

Whenever another creature dies, you may gain 1 life.

Destroy all creatures. They can't be regenerated. Draw a card for each creature destroyed this way.

Cycling {3}{B}{B} ({3}{B}{B}, Discard this card: Draw a card.)

When you cycle Decree of Pain, all creatures get -2/-2 until end of turn.

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

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

As long as Filth is in your graveyard and you control a Swamp, creatures you control have swampwalk.

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

Deathtouch

Whenever Grave Titan enters the battlefield or attacks, create two 2/2 black Zombie creature tokens.

When Gray Merchant of Asphodel enters the battlefield, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Destroy target creature or planeswalker.

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.

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

Choose a creature type. Destroy all creatures that aren't of the chosen type.

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)

Equip {0}

When Liliana's Contract enters the battlefield, you draw four cards and you lose 4 life.

At the beginning of your upkeep, if you control four or more Demons with different names, you win the game.

Each player exiles all creature cards from their graveyard, then sacrifices all creatures they control, then puts all cards they exiled this way onto the battlefield.

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

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

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.

Whenever a nontoken creature you control dies, Midnight Reaper deals 1 damage to you and you draw a card.

{T}: Add {C}.

{1}, {T}, Sacrifice Mind Stone: Draw a card.

{B}: Nantuko Shade gets +1/+1 until end of turn.

{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.

{1}{B}, {T}: Target opponent discards a card. Then if that player has no cards in hand, flip Nezumi Shortfang.

At the beginning of each opponent's upkeep, that player loses 1 life for each card fewer than three in their hand.

{T}: Add {C}.

{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

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.

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

Rat offering (You may cast this card any time you could cast an instant by sacrificing a Rat and paying the difference in mana costs between this and the sacrificed Rat. Mana cost includes color.)

Whenever a permanent is put into an opponent's graveyard, that player loses 1 life.

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.)

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

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.

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.

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

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.

At the beginning of each opponent's upkeep, that player sacrifices a creature.

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.

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)

Until end of turn, creatures target player controls lose all abilities and have base power and toughness 0/2.

({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.

{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.)

Deathtouch

When Thorn of the Black Rose enters the battlefield, you become the monarch.

Equipped creature has "{2}, {T}: This creature deals 1 damage to any target" and "Whenever a creature dies, untap this creature."

Whenever a Shaman creature enters the battlefield, you may attach Thornbite Staff to it.

Equip {4}

Ninjutsu {2}{B} ({2}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)

Whenever Throat Slitter deals combat damage to a player, destroy target nonblack creature that player controls.

As an additional cost to cast this spell, pay X life.

All creatures get -X/-X until end of turn.

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

Enchant land

Enchanted land has "{T}, Pay 1 life: Draw a card."

Whenever Zulaport Cutthroat or another creature you control dies, each opponent loses 1 life and you gain 1 life.