Headless Rider

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

A-Skull Skaab

Exploit (When this creature enters the battlefield, you may sacrifice a creature.)
Whenever a creature you control exploits a creature, create a 2/2 black Zombie creature token.

Bladestitched Skaab

Necroduality

Whenever a nontoken Zombie enters the battlefield under your control, create a token that's a copy of that creature.

Ice Tunnel

({T}: Add {U} or {B}.)
Ice Tunnel enters the battlefield tapped.

Snow-Covered Swamp

Shambling Ghast

When Shambling Ghast dies, choose one —
• Brave the Stench — Target creature an opponent controls gets -1/-1 until end of turn.
• Search the Body — Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Champion of the Perished

Whenever another Zombie enters the battlefield under your control, put a +1/+1 counter on Champion of the Perished.

Raise Dead

Return target creature card from your graveyard to your hand.

Priest of the Haunted Edge

{T}, Sacrifice Priest of the Haunted Edge: Target creature gets -X/-X until end of turn, where X is the number of snow lands you control. Activate only as a sorcery.

Archghoul of Thraben

Whenever Archghoul of Thraben or another Zombie you control dies, look at the top card of your library. If it's a Zombie card, you may reveal it and put it into your hand. If you don't put the card into your hand, you may put it into your graveyard.

Murder

Overcharged Amalgam

Flash
Flying
Exploit (When this creature enters the battlefield, you may sacrifice a creature.)
When Overcharged Amalgam exploits a creature, counter target spell, activated ability, or triggered ability.

Fell Stinger

Deathtouch
Exploit (When this creature enters the battlefield, you may sacrifice a creature.)
When Fell Stinger exploits a creature, target player draws two cards and loses 2 life.