Sign in Blood

Target player draws two cards and loses 2 life.

Woe Strider

When Woe Strider enters, create a 0/1 white Goat creature token.
Sacrifice another creature: Scry 1.
Escape—{3}{B}{B}, Exile four other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Woe Strider escapes with two +1/+1 counters on it.

Yahenni, Undying Partisan

Haste
Whenever a creature an opponent controls dies, put a +1/+1 counter on Yahenni, Undying Partisan.
Sacrifice another creature: Yahenni gains indestructible until end of turn.

High Market

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

Blood Artist

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

Kaya's Ghostform

Enchant creature or planeswalker you control
When enchanted permanent dies or is put into exile, return that card to the battlefield under your control.

Nimblewright Schematic

When Nimblewright Schematic enters or is put into a graveyard from the battlefield, create a 1/1 colorless Construct artifact creature token.

Tergrid's Lantern

{T}: Target player loses 3 life unless they sacrifice a nonland permanent or discard a card.
{3}{B}: Untap Tergrid's Lantern.

Tergrid, God of Fright

Menace
Whenever an opponent sacrifices a nontoken permanent or discards a permanent card, you may put that card from a graveyard onto the battlefield under your control.

Tergrid, God of Fright // Tergrid's Lantern

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Prowling Geistcatcher

Whenever you sacrifice another creature, exile it. If that creature was a token, put a +1/+1 counter on Prowling Geistcatcher.
When Prowling Geistcatcher leaves the battlefield, return each card exiled with it to the battlefield under your control.

Dreadhorde Invasion

At the beginning of your upkeep, you lose 1 life and amass Zombies 1. (Put a +1/+1 counter on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)
Whenever a Zombie token you control with power 6 or greater attacks, it gains lifelink until end of turn.

Field of Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Field of Ruin: Destroy target nonbasic land an opponent controls. Each player searches their library for a basic land card, puts it onto the battlefield, then shuffles.

Zulaport Cutthroat

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

Grim Haruspex

Morph {B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
Whenever another nontoken creature you control dies, draw a card.

Myriad Landscape

Myriad Landscape enters 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.

Tragic Slip

Target creature gets -1/-1 until end of turn.
Morbid — That creature gets -13/-13 until end of turn instead if a creature died this turn.

Cryptic Caves

{T}: Add {C}.
{1}, {T}, Sacrifice Cryptic Caves: Draw a card. Activate only if you control five or more lands.

Ob Nixilis, Unshackled

Flying, trample
Whenever an opponent searches their library, that player sacrifices a creature and loses 10 life.
Whenever another creature dies, put a +1/+1 counter on Ob Nixilis, Unshackled.

Polluted Mire

Polluted Mire enters tapped.
{T}: Add {B}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Swift End

Destroy target creature or planeswalker. You lose 2 life. (Then exile this card. You may cast the creature later from exile.)

Murderous Rider

Lifelink
When Murderous Rider dies, put it on the bottom of its owner's library.

Murderous Rider // Swift End

Ravenous Chupacabra

When Ravenous Chupacabra enters, destroy target creature an opponent controls.

Ghoulish Procession

Whenever one or more nontoken creatures die, create a 2/2 black Zombie creature token with decayed. This ability triggers only once each turn. (A creature with decayed can't block. When it attacks, sacrifice it at end of combat.)

Nim Deathmantle

Equipped creature gets +2/+2, has intimidate, and is a black Zombie. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a nontoken creature is put into your graveyard from the battlefield, you may pay {4}. If you do, return that card to the battlefield and attach Nim Deathmantle to it.
Equip {4}

Dire Fleet Hoarder

When Dire Fleet Hoarder dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Deadly Tempest

Destroy all creatures. Each player loses life equal to the number of creatures they controlled that were destroyed this way.

Midnight Reaper

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

Plaguecrafter

When Plaguecrafter enters, each player sacrifices a creature or planeswalker. Each player who can't discards a card.

Leaden Myr

Swamp

Mortuary Mire

Mortuary Mire enters tapped.
When Mortuary Mire enters, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.

Elderfang Disciple

When Elderfang Disciple enters, each opponent discards a card.

Witch's Cottage

({T}: Add {B}.)
Witch's Cottage enters tapped unless you control three or more other Swamps.
When Witch's Cottage enters untapped, you may put target creature card from your graveyard on top of your library.

Undying Evil

Target creature gains undying until end of turn. (When it 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.)

Servo Schematic

When Servo Schematic enters or is put into a graveyard from the battlefield, create a 1/1 colorless Servo artifact creature token.

Mycosynth Wellspring

When Mycosynth Wellspring enters or is put into a graveyard from the battlefield, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Altar's Reap

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

Drownyard Temple

{T}: Add {C}.
{3}: Return Drownyard Temple from your graveyard to the battlefield tapped.

Sifter of Skulls

Devoid (This card has no color.)
Whenever another nontoken creature you control dies, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add {C}." ({C} represents colorless mana.)

Barren Moor

Barren Moor enters tapped.
{T}: Add {B}.
Cycling {B} ({B}, Discard this card: Draw a card.)

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.
II — Each opponent discards a card.
III — Put target creature or planeswalker card from a graveyard onto the battlefield under your control.

Bloodsoaked Champion

Bloodsoaked Champion can't block.
Raid — {1}{B}: Return Bloodsoaked Champion from your graveyard to the battlefield. Activate only if you attacked this turn.

Gray Merchant of Asphodel

When Gray Merchant of Asphodel 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.)

Soul Shatter

Each opponent sacrifices a creature or planeswalker with the highest mana value among creatures and planeswalkers they control.

Charcoal Diamond

Charcoal Diamond enters tapped.
{T}: Add {B}.

Merciless Executioner

When Merciless Executioner enters, each player sacrifices a creature.

Prized Statue

When Prized Statue enters or is put into a graveyard from the battlefield, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Blighted Fen

{T}: Add {C}.
{4}{B}, {T}, Sacrifice Blighted Fen: Target opponent sacrifices a creature.

Reassembling Skeleton

{1}{B}: Return Reassembling Skeleton from your graveyard to the battlefield tapped.

Burglar Rat

When Burglar Rat enters, each opponent discards a card.

Memorial to Folly

Memorial to Folly enters tapped.
{T}: Add {B}.
{2}{B}, {T}, Sacrifice Memorial to Folly: Return target creature card from your graveyard to your hand.

Desert of the Glorified

Desert of the Glorified enters tapped.
{T}: Add {B}.
Cycling {1}{B} ({1}{B}, Discard this card: Draw a card.)

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Meteor Golem

When Meteor Golem enters, destroy target nonland permanent an opponent controls.

Fallen Ideal

Enchant creature
Enchanted creature has flying and "Sacrifice a creature: This creature gets +2/+1 until end of turn."
When Fallen Ideal is put into a graveyard from the battlefield, return Fallen Ideal to its owner's hand.

Ancient Craving

You draw three cards and you lose 3 life.

Fleshbag Marauder

When Fleshbag Marauder enters, each player sacrifices a creature.

Mutilate

All creatures get -1/-1 until end of turn for each Swamp you control.

Tenacious Dead

When Tenacious Dead dies, you may pay {1}{B}. If you do, return it to the battlefield tapped under its owner's control.

Diabolic Tutor

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

Carrier Thrall

When Carrier Thrall dies, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add {C}."

Smallpox

Each player loses 1 life, discards a card, sacrifices a creature, then sacrifices a land.

Hagra Broodpit

Hagra Broodpit enters tapped.
{T}: Add {B}.

Hagra Mauling

This spell costs {1} less to cast if an opponent controls no basic lands.
Destroy target creature.

Hagra Mauling // Hagra Broodpit

Haunted Fengraf

{T}: Add {C}.
{3}, {T}, Sacrifice Haunted Fengraf: Return a creature card at random from your graveyard to your hand.

Cabal Stronghold

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

Unearth

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Falkenrath Noble

Flying
Whenever Falkenrath Noble or another creature dies, target player loses 1 life and you gain 1 life.

Ornithopter of Paradise

Omen of the Dead

Flash
When Omen of the Dead enters, return target creature card from your graveyard to your hand.
{2}{B}, Sacrifice Omen of the Dead: Scry 2.

Dunes of the Dead

{T}: Add {C}.
When Dunes of the Dead is put into a graveyard from the battlefield, create a 2/2 black Zombie creature token.

Ever After

Return up to two target creature cards from your graveyard to the battlefield. Each of those creatures is a black Zombie in addition to its other colors and types. Put Ever After on the bottom of its owner's library.

Nihil Spellbomb

{T}, Sacrifice Nihil Spellbomb: Exile target player's graveyard.
When Nihil Spellbomb is put into a graveyard from the battlefield, you may pay {B}. If you do, draw a card.

Infernal Grasp

Destroy target creature. You lose 2 life.

Braids, Arisen Nightmare

At the beginning of your end step, you may sacrifice an artifact, creature, enchantment, land, or planeswalker. If you do, each opponent may sacrifice a permanent that shares a card type with it. For each opponent who doesn't, that player loses 2 life and you draw a card.

Disciple of Bolas

When Disciple of Bolas enters, sacrifice another creature. You gain X life and draw X cards, where X is that creature's power.

Demonic Lore

When Demonic Lore enters, draw three cards.
At the beginning of your end step, you lose 2 life for each card in your hand.

Treacherous Blessing

When Treacherous Blessing enters, draw three cards.
Whenever you cast a spell, you lose 1 life.
When Treacherous Blessing becomes the target of a spell or ability, sacrifice it.

Braids's Frightful Return

Read ahead (Choose a chapter and start with that many lore counters. Add one after your draw step. Skipped chapters don't trigger. Sacrifice after III.)
I — You may sacrifice a creature. If you do, each opponent discards a card.
II — Return target creature card from your graveyard to your hand.
III — Target opponent may sacrifice a nonland, nontoken permanent. If they don't, they lose 2 life and you draw a card.

Butcher of Malakir

Flying
Whenever Butcher of Malakir or another creature you control dies, each opponent sacrifices a creature.

Defile

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

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Sol Ring

Nested Shambler

When Nested Shambler dies, create X tapped 1/1 green Squirrel creature tokens, where X is Nested Shambler's power.

Black Market

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

Bojuka Bog

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