Endless Ranks of the Dead

At the beginning of your upkeep, create X 2/2 black Zombie creature tokens, where X is half the number of Zombies you control, rounded down.

Fleshbag Marauder

When Fleshbag Marauder enters, each player sacrifices a creature of their choice.

Urborg, Tomb of Yawgmoth

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

Cleaver Skaab

{3}, {T}, Sacrifice another Zombie: Create two tokens that are copies of the sacrificed creature.

Watery Grave

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

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Rooftop Storm

You may pay {0} rather than pay the mana cost for Zombie creature spells you cast.

Empty the Laboratory

Sacrifice X Zombies, then reveal cards from the top of your library until you reveal a number of Zombie creature cards equal to the number of Zombies sacrificed this way. Put those cards onto the battlefield and the rest on the bottom of your library in a random order.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

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.)

Unstoppable Slasher

Deathtouch
Whenever Unstoppable Slasher deals combat damage to a player, they lose half their life, rounded up.
When Unstoppable Slasher dies, if it had no counters on it, return it to the battlefield tapped under its owner's control with two stun counters on it.

Headless Rider

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

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.

Roaming Throne

Ward {2}
As Roaming Throne enters, choose a creature type.
Roaming Throne is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Command Tower

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

Cemetery Reaper

Other Zombie creatures you control get +1/+1.
{2}{B}, {T}: Exile target creature card from a graveyard. Create a 2/2 black Zombie creature token.

Patchwork Banner

As Patchwork Banner enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{T}: Add one mana of any color.

Arcane Signet

Gleaming Overseer

When Gleaming Overseer enters, 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.)
Zombie tokens you control have hexproof and menace.

Gloomlake Verge

{T}: Add {U}.
{T}: Add {B}. Activate only if you control an Island or a Swamp.

Warren Soultrader

Pay 1 life, Sacrifice another creature: Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

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.

Gisa and Geralf

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

Ashnod's Altar

Withering Torment

Destroy target creature or enchantment. You lose 2 life.

Accursed Marauder

When Accursed Marauder enters, each player sacrifices a nontoken creature of their choice.

Noxious Ghoul

Whenever Noxious Ghoul or another Zombie enters, all non-Zombie creatures get -1/-1 until end of turn.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

Champion of the Perished

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

Unclaimed Territory

As Unclaimed Territory enters, 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.

Midnight Reaper

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

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Wilhelt, the Rotcleaver

Whenever another Zombie you control dies, if it didn't have decayed, create a 2/2 black Zombie creature token with decayed. (It can't block. When it attacks, sacrifice it at end of combat.)
At the beginning of your end step, you may sacrifice a Zombie. If you do, draw a card.

Gravecrawler

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

Drowned Catacomb

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

Death Baron

Skeletons you control and other Zombies you control get +1/+1 and have deathtouch. (Any amount of damage they deal to a creature is enough to destroy it.)

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.

Shipwreck Marsh

Shipwreck Marsh enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Morphic Pool

Morphic Pool enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Necroduality

Whenever a nontoken Zombie you control enters, create a token that's a copy of that creature.

Three Tree City

As Three Tree City enters, choose a creature type.
{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to the number of creatures you control of the chosen type.

Zombie Apocalypse

Return all Zombie creature cards from your graveyard to the battlefield tapped, then destroy all Humans.

Demonic Tutor

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

Negate

Undead Warchief

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

Diregraf Captain

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