Necrogoyf

Necrogoyf's power is equal to the number of creature cards in all graveyards.
At the beginning of each player's upkeep, that player discards a card.
Madness {1}{B}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Sewer Nemesis

As Sewer Nemesis enters, choose a player.
Sewer Nemesis's power and toughness are each equal to the number of cards in the chosen player's graveyard.
Whenever the chosen player casts a spell, that player mills a card.

Another Chance

You may mill two cards. Then return up to two creature cards from your graveyard to your hand. (To mill two cards, put the top two cards of your library into your graveyard.)

Lord of Extinction

Lord of Extinction's power and toughness are each equal to the number of cards in all graveyards.

Mulch

Reveal the top four cards of your library. Put all land cards revealed this way into your hand and the rest into your graveyard.

Varolz, the Scar-Striped

Each creature card in your graveyard has scavenge. The scavenge cost is equal to its mana cost. (Exile a creature card from your graveyard and pay its mana cost: Put a number of +1/+1 counters equal to that card's power on target creature. Scavenge only as a sorcery.)
Sacrifice another creature: Regenerate Varolz, the Scar-Striped.

Mortivore

Mortivore's power and toughness are each equal to the number of creature cards in all graveyards.
{B}: Regenerate Mortivore. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Ripples of Undeath

At the beginning of your first main phase, mill three cards. Then you may pay {1} and 3 life. If you do, put a card from among those cards into your hand.

Atrocious Experiment

Target player mills two cards, draws two cards, and loses 2 life. (To mill a card, a player puts the top card of their library into their graveyard.)

Tato Farmer

Landfall — Whenever a land you control enters, you may get two rad counters.
{T}: Put target land card in a graveyard that was milled this turn onto the battlefield under your control tapped.

Hedge Shredder

Whenever Hedge Shredder attacks, you may mill two cards.
Whenever one or more land cards are put into your graveyard from your library, put them onto the battlefield tapped.
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

Cadaver Lab

When you unlock this door, return target creature card from your graveyard to your hand.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Defiled Crypt

Whenever one or more cards leave your graveyard, create a 2/2 black Horror enchantment creature token. This ability triggers only once each turn.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Defiled Crypt // Cadaver Lab

Thran Vigil

Whenever one or more artifact and/or creature cards leave your graveyard during your turn, put a +1/+1 counter on target creature you control.

Kagha, Shadow Archdruid

Whenever Kagha, Shadow Archdruid attacks, it gains deathtouch until end of turn. Mill two cards. (Put the top two cards of your library into your graveyard.)
Once during each of your turns, you may play a land or cast a permanent spell from among cards in your graveyard that were put there from your library this turn.

Acolyte of Affliction

When Acolyte of Affliction enters, mill two cards, then you may return a permanent card from your graveyard to your hand.

Insidious Roots

Creature tokens you control have "{T}: Add one mana of any color."
Whenever one or more creature cards leave your graveyard, create a 0/1 green Plant creature token, then put a +1/+1 counter on each Plant you control.

Willow Geist

Trample
Whenever one or more cards leave your graveyard, put a +1/+1 counter on Willow Geist.
When Willow Geist dies, you gain life equal to its power.

Soul Enervation

Flash
When Soul Enervation enters, target creature gets -4/-4 until end of turn.
Whenever one or more creature cards leave your graveyard, each opponent loses 1 life and you gain 1 life.

Screeching Scorchbeast

Flying, menace
Whenever Screeching Scorchbeast attacks, each player gets two rad counters.
Whenever one or more nonland cards are milled, you may create that many 2/2 black Zombie Mutant creature tokens. Do this only once each turn.

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.)

Animal Magnetism

Reveal the top five cards of your library. An opponent chooses a creature card from among them. Put that card onto the battlefield and the rest into your graveyard.

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.)

Skeleton Crew

Each other creature you control that's a Skeleton or Pirate gets +1/+1.
Whenever one or more creature cards leave your graveyard, create a 2/2 black Skeleton Pirate creature token. (This ability triggers only from the battlefield.)
{5}{B}: Return Skeleton Crew from your graveyard to the battlefield tapped.

Aftermath Analyst

When Aftermath Analyst enters, mill three cards.
{3}{G}, Sacrifice Aftermath Analyst: Return all land cards from your graveyard to the battlefield tapped.

Chalk Outline

Whenever one or more creature cards leave your graveyard, create a 2/2 white and blue Detective creature token, then investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Circle of the Land Druid

When Circle of the Land Druid enters, you may mill four cards. (You may put the top four cards of your library into your graveyard.)
Natural Recovery — When Circle of the Land Druid dies, return target land card from your graveyard to your hand.

Angel of Suffering

Flying
If damage would be dealt to you, prevent that damage and mill twice that many cards.