Noxious Ghoul

Whenever this creature or another Zombie enters, all non-Zombie creatures get -1/-1 until end of turn.

Swamp

Undead Warchief

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

Balthor the Defiled

Minion creatures get +1/+1.
{B}{B}{B}, Exile Balthor: Each player returns all black and all red creature cards from their graveyard to the battlefield.

Putrid Imp

Discard a card: This creature gains flying until end of turn.
Threshold — As long as seven or more cards are in your graveyard, this creature gets +1/+1 and can't block.

Gempalm Polluter

Cycling {B}{B} ({B}{B}, Discard this card: Draw a card.)
When you cycle this card, you may have target player lose life equal to the number of Zombies on the battlefield.

Carrion Feeder

This creature can't block.
Sacrifice a creature: Put a +1/+1 counter on this creature.

Shepherd of Rot

{T}: Each player loses 1 life for each Zombie on the battlefield.

Urborg

{T}: Add {B}.
{T}: Target creature loses first strike or swampwalk until end of turn.

Dark Ritual

Snow-Covered Swamp

Lord of the Undead

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

Sol Ring

Withered Wretch

Festering Goblin

When this creature dies, target creature gets -1/-1 until end of turn.

Grave Defiler

When this creature enters, reveal the top four cards of your library. Put all Zombie cards revealed this way into your hand and the rest on the bottom of your library in any order.
{1}{B}: Regenerate this creature.

Vengeful Dead

Whenever this creature or another Zombie dies, each opponent loses 1 life.

Soulless One

Soulless One's power and toughness are each equal to the number of Zombies on the battlefield plus the number of Zombie cards in all graveyards.