Damnation

Destroy all creatures. They can't be regenerated.

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature.

Duress

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

Rise of the Dark Realms

Put all creature cards from all graveyards onto the battlefield under your control.

Bad Moon

Headless Rider

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

Diabolic Tutor

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

Ebondeath, Dracolich

Flash
Flying
Ebondeath, Dracolich enters the battlefield tapped.
You may cast Ebondeath, Dracolich from your graveyard if a creature not named Ebondeath, Dracolich died this turn.

Swamp

Death Baron

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

Gravecrawler

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

Exquisite Blood

Whenever an opponent loses life, you gain that much life.

Darkness

Prevent all combat damage that would be dealt this turn.

Mikaeus, the Unhallowed

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a Human deals damage to you, destroy it.
Other non-Human creatures you control get +1/+1 and have undying. (When a creature with undying dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

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.

Undead Warchief

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

Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent or discards a card.

Zombie

Skithiryx, the Blight Dragon

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{B}: Skithiryx, the Blight Dragon gains haste until end of turn.
{B}{B}: Regenerate Skithiryx.

Grim Tutor

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

The Meathook Massacre

When The Meathook Massacre enters the battlefield, each creature gets -X/-X until end of turn.
Whenever a creature you control dies, each opponent loses 1 life.
Whenever a creature an opponent controls dies, you gain 1 life.

Lord of the Undead

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

Wall of Bone

Defender (This creature can't attack.)
{B}: Regenerate Wall of Bone. (The next time this creature would be destroyed this turn, it isn't. Instead tap it, remove all damage from it, and remove it from combat.)

Drudge Skeletons

{B}: Regenerate Drudge Skeletons. (The next time this creature would be destroyed this turn, it isn't. Instead tap it, remove all damage from it, and remove it from combat.)