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.

Tidehollow Sculler

When Tidehollow Sculler enters the battlefield, target opponent reveals their hand and you choose a nonland card from it. Exile that card.
When Tidehollow Sculler leaves the battlefield, return the exiled card to its owner's hand.

Concealed Courtyard

Concealed Courtyard enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {W} or {B}.

Ashen Ghoul

Haste
{B}: Return Ashen Ghoul from your graveyard to the battlefield. Activate only during your upkeep and only if three or more creature cards are above Ashen Ghoul.

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Drowned Catacomb

Drowned Catacomb enters the battlefield tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Custodi Lich

When Custodi Lich enters the battlefield, you become the monarch.
Whenever you become the monarch, target player sacrifices a creature.

Midnight Reaper

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

Thoughtseize

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

Shepherd of Rot

{T}: Each player loses 1 life for each Zombie on the battlefield.

Skullclamp

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

Bladestitched Skaab

Damn

Destroy target creature. A creature destroyed this way can't be regenerated.
Overload {2}{W}{W} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Duress

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

Gray Merchant of Asphodel

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.)

Mox Jet

Windswept Heath

{T}, Pay 1 life, Sacrifice Windswept Heath: Search your library for a Forest or Plains card, put it onto the battlefield, then shuffle.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Raffine's Tower

({T}: Add {W}, {U}, or {B}.)
Raffine's Tower enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Gravecrawler

Gravecrawler can't block.
You may cast Gravecrawler from your graveyard as long as you control a Zombie.

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Karakas

{T}: Add {W}.
{T}: Return target legendary creature to its owner's hand.

Prismatic Ending

Converge — Exile target nonland permanent if its mana value is less than or equal to the number of colors of mana spent to cast this spell.

Dread Wanderer

Dread Wanderer enters the battlefield tapped.
{2}{B}: Return Dread Wanderer from your graveyard to the battlefield. Activate only as a sorcery and only if you have one or fewer cards in hand.

Jadar, Ghoulcaller of Nephalia

At the beginning of your end step, if you control no creatures with decayed, create a 2/2 black Zombie creature token with decayed. (It can't block. When it attacks, sacrifice it at end of combat.)

Carrion Feeder

Carrion Feeder can't block.
Sacrifice a creature: Put a +1/+1 counter on Carrion Feeder.

Recurring Nightmare

Sacrifice a creature, Return Recurring Nightmare to its owner's hand: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.

Withered Wretch

Godless Shrine

({T}: Add {W} or {B}.)
As Godless Shrine enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Hive of the Eye Tyrant

If you control two or more other lands, Hive of the Eye Tyrant enters the battlefield tapped.
{T}: Add {B}.
{3}{B}: Until end of turn, Hive of the Eye Tyrant becomes a 3/3 black Beholder creature with menace and "Whenever this creature attacks, exile target card from defending player's graveyard." It's still a land.

Wasteland

{T}: Add {C}.
{T}, Sacrifice Wasteland: Destroy target nonbasic land.

Unsettled Mariner

Changeling (This card is every creature type.)
Whenever you or a permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {1}.

Mire Triton

Deathtouch
When Mire Triton enters the battlefield, mill two cards and you gain 2 life.

Lord of the Accursed

Other Zombies you control get +1/+1.
{1}{B}, {T}: All Zombies gain menace until end of turn.

Undead Augur

Whenever Undead Augur or another Zombie you control dies, you draw a card and you lose 1 life.

Isolated Chapel

Isolated Chapel enters the battlefield tapped unless you control a Plains or a Swamp.
{T}: Add {W} or {B}.

Mother of Runes

{T}: Target creature you control gains protection from the color of your choice until end of turn.

Castle Locthwain

Castle Locthwain enters the battlefield tapped unless you control a Swamp.
{T}: Add {B}.
{1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.

Dark Ritual

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Mirror Entity

Changeling (This card is every creature type.)
{X}: Until end of turn, creatures you control have base power and toughness X/X and gain all creature types.

Diregraf Captain

Deathtouch
Other Zombie creatures you control get +1/+1.
Whenever another Zombie you control dies, target opponent loses 1 life.

Geralf, Visionary Stitcher

Zombies you control have flying.
{U}, {T}, Sacrifice another nontoken creature: Create an X/X blue Zombie creature token, where X is the sacrificed creature's toughness.

Zombie Master

Other Zombie creatures have swampwalk. (They can't be blocked as long as defending player controls a Swamp.)
Other Zombies have "{B}: Regenerate this permanent."

Undead Butler

When Undead Butler enters the battlefield, mill three cards. (Put the top three cards of your library into your graveyard.)
When Undead Butler dies, you may exile it. When you do, return target creature card from your graveyard to your hand.

Watery Grave

({T}: Add {U} or {B}.)
As Watery Grave enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Liliana, the Last Hope

+1: Up to one target creature gets -2/-1 until your next turn.
−2: Mill two cards, then you may return a creature card from your graveyard to your hand.
−7: You get an emblem with "At the beginning of your end step, create X 2/2 black Zombie creature tokens, where X is two plus the number of Zombies you control."

Wayward Servant

Whenever another Zombie enters the battlefield under your control, each opponent loses 1 life and you gain 1 life.

Plaguebearer

{X}{X}{B}: Destroy target nonblack creature with mana value X.

Fallen Shinobi

Ninjutsu {2}{U}{B} ({2}{U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Fallen Shinobi deals combat damage to a player, that player exiles the top two cards of their library. Until end of turn, you may play those cards without paying their mana costs.

White Plume Adventurer

When White Plume Adventurer enters the battlefield, you take the initiative.
At the beginning of each opponent's upkeep, untap a creature you control. If you've completed a dungeon, untap all creatures you control instead.

Bloodstained Mire

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Grave Defiler

When Grave Defiler enters the battlefield, reveal the top four cards of your library. Put all Zombie cards revealed this way into your hand and the rest on the bottom of your library in any order.
{1}{B}: Regenerate Grave Defiler.

Archghoul of Thraben

Whenever Archghoul of Thraben or another Zombie you control dies, look at the top card of your library. If it's a Zombie card, you may reveal it and put it into your hand. If you don't put the card into your hand, you may put it into your graveyard.

Aether Vial

At the beginning of your upkeep, you may put a charge counter on Aether Vial.
{T}: You may put a creature card with mana value equal to the number of charge counters on Aether Vial from your hand onto the battlefield.

Cavern of Souls

As Cavern of Souls enters the battlefield, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Darkslick Shores

Darkslick Shores enters the battlefield tapped unless you control two or fewer other lands.
{T}: Add {U} or {B}.

Diregraf Colossus

Diregraf Colossus enters the battlefield with a +1/+1 counter on it for each Zombie card in your graveyard.
Whenever you cast a Zombie spell, create a tapped 2/2 black Zombie creature token.

Lord of the Undead

Other Zombie creatures get +1/+1.
{1}{B}, {T}: Return target Zombie card from your graveyard to your hand.

Black Lotus

{T}, Sacrifice Black Lotus: Add three mana of any one color.

The Scarab God

At the beginning of your upkeep, each opponent loses X life and you scry X, where X is the number of Zombies you control.
{2}{U}{B}: Exile target creature card from a graveyard. Create a token that's a copy of it, except it's a 4/4 black Zombie.
When The Scarab God dies, return it to its owner's hand at the beginning of the next end step.

Misty Rainforest

{T}, Pay 1 life, Sacrifice Misty Rainforest: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

Undead Warchief

Zombie spells you cast cost {1} less to cast.
Zombie creatures you control get +2/+1.

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Urza's Saga gains "{T}: Add {C}."
II — Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Marsh Flats

{T}, Pay 1 life, Sacrifice Marsh Flats: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Swamp

Shadowspear

Equipped creature gets +1/+1 and has trample and lifelink.
{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.
Equip {2}

Stitcher's Supplier

When Stitcher's Supplier enters the battlefield or dies, mill three cards.

Scrubland

Orcish Bowmasters

Flash
When Orcish Bowmasters enters the battlefield and whenever an opponent draws a card except the first one they draw in each of their draw steps, Orcish Bowmasters deals 1 damage to any target. Then amass Orcs 1.

Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Relentless Dead

Menace (This creature can't be blocked except by two or more creatures.)
When Relentless Dead dies, you may pay {B}. If you do, return it to its owner's hand.
When Relentless Dead dies, you may pay {X}. If you do, return another target Zombie creature card with mana value X from your graveyard to the battlefield.

Lurrus of the Dream-Den

Companion — Each permanent card in your starting deck has mana value 2 or less. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
Lifelink
Once during each of your turns, you may cast a permanent spell with mana value 2 or less from your graveyard.

Death Baron

Skeletons you control and other Zombies you control get +1/+1 and have deathtouch.

Contamination

At the beginning of your upkeep, sacrifice Contamination unless you sacrifice a creature.
If a land is tapped for mana, it produces {B} instead of any other type and amount.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Verdant Catacombs

{T}, Pay 1 life, Sacrifice Verdant Catacombs: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Liliana of the Veil

+1: Each player discards a card.
−2: Target player sacrifices a creature.
−6: Separate all permanents target player controls into two piles. That player sacrifices all permanents in the pile of their choice.

Mutavault

{T}: Add {C}.
{1}: Mutavault becomes a 2/2 creature with all creature types until end of turn. It's still a land.

Mausoleum Secrets

Undergrowth — Search your library for a black card with mana value less than or equal to the number of creature cards in your graveyard, reveal it, put it into your hand, then shuffle.

Flooded Strand

{T}, Pay 1 life, Sacrifice Flooded Strand: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Gisa and Geralf

When Gisa and Geralf enters the battlefield, mill four cards.
Once during each of your turns, you may cast a Zombie creature spell from your graveyard.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Hymn to Tourach

Target player discards two cards at random.

Headless Rider

Whenever Headless Rider or another nontoken Zombie you control dies, create a 2/2 black Zombie creature token.

Plague Belcher

Menace
When Plague Belcher enters the battlefield, put two -1/-1 counters on target creature you control.
Whenever another Zombie you control dies, each opponent loses 1 life.

Corpse Knight

Whenever another creature enters the battlefield under your control, each opponent loses 1 life.

Cryptbreaker

{1}{B}, {T}, Discard a card: Create a 2/2 black Zombie creature token.
Tap three untapped Zombies you control: You draw a card and you lose 1 life.

Arid Mesa

{T}, Pay 1 life, Sacrifice Arid Mesa: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Gempalm Polluter

Cycling {B}{B} ({B}{B}, Discard this card: Draw a card.)
When you cycle Gempalm Polluter, you may have target player lose life equal to the number of Zombies on the battlefield.

Underground Sea

Inquisition of Kozilek

Target player reveals their hand. You choose a nonland card from it with mana value 3 or less. That player discards that card.

Champion of the Perished

Whenever another Zombie enters the battlefield under your control, put a +1/+1 counter on Champion of the Perished.

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.