Wall of Limbs

Defender (This creature can't attack.)
Whenever you gain life, put a +1/+1 counter on this creature.
{5}{B}{B}, Sacrifice this creature: Target player loses X life, where X is this creature's power.

Sanitarium Skeleton

{2}{B}: Return this card from your graveyard to your hand.

Swamp

Crow of Dark Tidings

Flying
When this creature enters or dies, mill two cards. (Put the top two cards of your library into your graveyard.)

Markov Dreadknight

Flying
{2}{B}, Discard a card: Put two +1/+1 counters on this creature.

Immortal Servitude

Return each creature card with mana value X from your graveyard to the battlefield.

Rottenheart Ghoul

When this creature dies, target player discards a card.

Mortivore

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

From Under the Floorboards

Madness {X}{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.)
Create three tapped 2/2 black Zombie creature tokens and you gain 3 life. If this spell's madness cost was paid, instead create X of those tokens and you gain X life.

Pale Rider of Trostad

Skulk (This creature can't be blocked by creatures with greater power.)
When this creature enters, discard a card.

Reassembling Skeleton

{1}{B}: Return this card from your graveyard to the battlefield tapped.

Insidious Mist

Hexproof, indestructible
This creature can't block and can't be blocked.
Whenever this creature attacks and isn't blocked, you may pay {2}{B}. If you do, transform it.

Elusive Tormentor

{1}, Discard a card: Transform this creature.

Elusive Tormentor // Insidious Mist

Rise from the Grave

Put target creature card from a graveyard onto the battlefield under your control. That creature is a black Zombie in addition to its other colors and types.

Shamble Back

Exile target creature card from a graveyard. Create a 2/2 black Zombie creature token. You gain 2 life.

Relentless Dead

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

Alms of the Vein

Target opponent loses 3 life and you gain 3 life.
Madness {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.)

Demon-Possessed Witch

When this creature transforms into Demon-Possessed Witch, you may destroy target creature.

Kindly Stranger

Delirium — {2}{B}: Transform this creature. Activate only if there are four or more card types among cards in your graveyard.

Kindly Stranger // Demon-Possessed Witch

March of the Returned

Return up to two target creature cards from your graveyard to your hand.

Biting Rain

All creatures get -2/-2 until end of turn.
Madness {2}{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.)

Rescue from the Underworld

As an additional cost to cast this spell, sacrifice a creature.
Choose target creature card in your graveyard. Return that card and the sacrificed card to the battlefield under your control at the beginning of your next upkeep. Exile Rescue from the Underworld.

Walking Corpse

Diabolic Tutor

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

Liliana's Indignation

Mill X cards. Target player loses 2 life for each creature card put into your graveyard this way.

Hound of the Farbogs

Delirium — This creature has menace as long as there are four or more card types among cards in your graveyard. (A creature with menace can't be blocked except by two or more creatures.)

Ghoulcaller's Accomplice

{3}{B}, Exile this card from your graveyard: Create a 2/2 black Zombie creature token. Activate only as a sorcery.