Have

Lively Dirge

Spree (Choose one or more additional costs.)
+ {1} — Search your library for a card, put it into your graveyard, then shuffle.
+ {2} — Return up to two creature cards with total mana value 4 or less from your graveyard to the battlefield.

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Insatiable Avarice

Spree (Choose one or more additional costs.)
+ {2} — Search your library for a card, then shuffle and put that card on top.
+ {B}{B} — Target player draws three cards and loses 3 life.

Universal Automaton

Changeling (This card is every creature type.)

Thought Vessel

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

Annihilate

Destroy target nonblack creature. It can't be regenerated.
Draw a card.

Loxodon Warhammer

Equipped creature gets +3/+0 and has trample and lifelink.
Equip {3}

Gutter Skulk

Bontu's Monument

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.

Graf Rats

At the beginning of combat on your turn, if you both own and control this creature and a creature named Midnight Scavengers, exile them, then meld them into Chittering Host.

Skullsnatcher

Ninjutsu {B} ({B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever this creature deals combat damage to a player, exile up to two target cards from that player's graveyard.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Kindred Dominance

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

Vraska's Fall

Each opponent sacrifices a creature or planeswalker of their choice and gets a poison counter.

Ambition's Cost

You draw three cards and you lose 3 life.

Seer's Sundial

Landfall — Whenever a land you control enters, you may pay {2}. If you do, draw a card.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Crypt Rats

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

Lost Vale

(Transforms from Dowsing Dagger.)
{T}: Add three mana of any one color.

Dowsing Dagger

When this Equipment enters, target opponent creates two 0/2 green Plant creature tokens with defender.
Equipped creature gets +2/+1.
Whenever equipped creature deals combat damage to a player, you may transform this Equipment.
Equip {2}

Dowsing Dagger // Lost Vale

Blightbelly Rat

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
When this creature dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Karumonix, the Rat King

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.

Blasted Landscape

{T}: Add {C}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Deathmask Nezumi

As long as you have seven or more cards in hand, this creature gets +2/+1 and has fear. (It can't be blocked except by artifact creatures and/or black creatures.)

Blade of Selves

Equipped creature has myriad. (Whenever it attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Equip {4}

Cabal Stronghold

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

Prismatic Lens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Marrow-Gnawer

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.

Defile

Target creature gets -1/-1 until end of turn for each Swamp you control.

Charcoal Diamond

This artifact enters tapped.
{T}: Add {B}.

Midnight Scavengers

When this creature enters, you may return target creature card with mana value 3 or less from your graveyard to your hand.
(Melds with Graf Rats.)

Rancid Rats

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.)

The Eldest Reborn

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Each opponent sacrifices a creature or planeswalker of their choice.
II — Each opponent discards a card.
III — Put target creature or planeswalker card from a graveyard onto the battlefield under your control.

Gray Merchant of Asphodel

When this creature enters, 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.)

Sword of Truth and Justice

Equipped creature gets +2/+2 and has protection from white and from blue.
Whenever equipped creature deals combat damage to a player, put a +1/+1 counter on a creature you control, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Equip {2}

Whisper of the Dross

Target creature gets -1/-1 until end of turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Worn Powerstone

This artifact enters tapped.
{T}: Add {C}{C}.

Swamp

Contaminated Bond

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Whenever enchanted creature attacks or blocks, its controller loses 3 life.

Heartless Pillage

Target opponent discards two cards.
Raid — If you attacked this turn, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Chittering Skitterling

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.

Essence Harvest

Target player loses X life and you gain X life, where X is the greatest power among creatures you control.

Ormendahl, Profane Prince

Westvale Abbey

{T}: Add {C}.
{5}, {T}, Pay 1 life: Create a 1/1 white and black Human Cleric creature token.
{5}, {T}, Sacrifice five creatures: Transform this land, then untap it.

Westvale Abbey // Ormendahl, Profane Prince

Costly Plunder

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards.

Core Prowler

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
When this creature dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Karn's Bastion

{T}: Add {C}.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Sol Ring

Nezumi Cutthroat

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

Changeling Outcast

Changeling (This card is every creature type.)
This creature can't block and can't be blocked.

Nezumi Informant

When this creature enters, each opponent discards a card.

Rat Colony

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

Drown in Ichor

Target creature gets -4/-4 until end of turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Staff of Nin

At the beginning of your upkeep, draw a card.
{T}: This artifact deals 1 damage to any target.