Empty the Pits

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Create X tapped 2/2 black Zombie creature tokens.

Phyrexian Reclamation

{1}{B}, Pay 2 life: Return target creature card from your graveyard to your hand.

Dakmor Salvage

Dakmor Salvage enters the battlefield tapped.
{T}: Add {B}.
Dredge 2 (If you would draw a card, you may mill two cards instead. If you do, return this card from your graveyard to your hand.)

Incarnation Technique

Demonstrate (When you cast this spell, you may copy it. If you do, choose an opponent to also copy it.)
Mill five cards, then return a creature card from your graveyard to the battlefield.

Mesmeric Orb

Whenever a permanent becomes untapped, that permanent's controller mills a card.

Unholy Grotto

{T}: Add {C}.
{B}, {T}: Put target Zombie card from your graveyard on top of your library.

Tormod's Crypt

{T}, Sacrifice Tormod's Crypt: Exile target player's graveyard.

Witch's Cottage

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

Dread

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Whenever a creature deals damage to you, destroy it.
When Dread is put into a graveyard from anywhere, shuffle it into its owner's library.

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.

Geier Reach Sanitarium

{T}: Add {C}.
{2}, {T}: Each player draws a card, then discards a card.

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad, the Grim deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Screams from Within

Enchant creature
Enchanted creature gets -1/-1.
When enchanted creature dies, return Screams from Within from your graveyard to the battlefield.

Snow-Covered Swamp

The Cauldron of Eternity

This spell costs {2} less to cast for each creature card in your graveyard.
Whenever a creature you control dies, put it on the bottom of its owner's library.
{2}{B}, {T}, Pay 2 life: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.

Gravecrawler

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

Volrath's Stronghold

{T}: Add {C}.
{1}{B}, {T}: Put target creature card from your graveyard on top of your library.

Gravespawn Sovereign

Tap five untapped Zombies you control: Put target creature card from a graveyard onto the battlefield under your control.

Stinkweed Imp

Flying
Whenever Stinkweed Imp deals combat damage to a creature, destroy that creature.
Dredge 5 (If you would draw a card, you may mill five cards instead. If you do, return this card from your graveyard to your hand.)

Tormod, the Desecrator

Whenever one or more cards leave your graveyard, create a tapped 2/2 black Zombie creature token.
Partner (You can have two commanders if both have partner.)

Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

Ashnod's Altar

Sanitarium Skeleton

{2}{B}: Return Sanitarium Skeleton from your graveyard to your hand.

Phyrexian Altar

Sacrifice a creature: Add one mana of any color.

Dread Summons

Each player mills X cards. For each creature card put into a graveyard this way, you create a tapped 2/2 black Zombie creature token.

Reassembling Skeleton

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

Drownyard Temple

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

Haunted Crossroads

{B}: Put target creature card from your graveyard on top of your library.

Oversold Cemetery

At the beginning of your upkeep, if you have four or more creature cards in your graveyard, you may return target creature card from your graveyard to your hand.

Golgari Thug

When Golgari Thug dies, put target creature card from your graveyard on top of your library.
Dredge 4 (If you would draw a card, you may mill four cards instead. If you do, return this card from your graveyard to your hand.)

Desecrated Tomb

Whenever one or more creature cards leave your graveyard, create a 1/1 black Bat creature token with flying.

Sibsig Muckdraggers

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
When Sibsig Muckdraggers enters the battlefield, return target creature card from your graveyard to your hand.

Kozilek, Butcher of Truth

When you cast this spell, draw four cards.
Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents.)
When Kozilek, Butcher of Truth is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

Victimize

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

Nightmare Void

Target player reveals their hand. You choose a card from it. That player discards that card.
Dredge 2 (If you would draw a card, you may mill two cards instead. If you do, return this card from your graveyard to your hand.)

Wake the Dead

Cast this spell only during combat on an opponent's turn.
Return X target creature cards from your graveyard to the battlefield. Sacrifice those creatures at the beginning of the next end step.

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

Arcane Signet

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

Command Tower

Codex Shredder

{T}: Target player mills a card. (They put the top card of their library into their graveyard.)
{5}, {T}, Sacrifice Codex Shredder: Return target card from your graveyard to your hand.