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.)

Diregraf Ghoul

Murder

Desecrated Tomb

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

Swamp

Costly Plunder

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards.

Gravedigger

When Gravedigger enters, you may return target creature card from your graveyard to your hand.

Carrion Feeder

Carrion Feeder can't block.
Sacrifice a creature: Put a +1/+1 counter on Carrion Feeder.

Graf Harvest

Zombies you control have menace. (They can't be blocked except by two or more creatures.)
{3}{B}, Exile a creature card from your graveyard: Create a 2/2 black Zombie creature token.

Liliana's Mastery

Zombies you control get +1/+1.
When Liliana's Mastery enters, create two 2/2 black Zombie creature tokens.

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.

Gravecrawler

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

Undead Augur

Whenever Undead Augur or another Zombie you control dies, you draw a card and you lose 1 life.

Diregraf Colossus

Diregraf Colossus enters with a +1/+1 counter on it for each Zombie card in your graveyard.
Whenever you cast a Zombie spell, create a tapped 2/2 black Zombie creature token.