Lord of the Accursed

Other Zombies you control get +1/+1.
{1}{B}, {T}: All Zombies gain menace until end of turn.

Stir the Sands

Create three 2/2 black Zombie creature tokens.
Cycling {3}{B} ({3}{B}, Discard this card: Draw a card.)
When you cycle Stir the Sands, create a 2/2 black Zombie creature token.

Swamp

Time to Reflect

Exile target creature that blocked or was blocked by a Zombie this turn.

Wayward Servant

Whenever another Zombie you control enters, each opponent loses 1 life and you gain 1 life.

Plains

Liliana's Mastery

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

Cradle of the Accursed

{T}: Add {C}.
{3}, {T}, Sacrifice Cradle of the Accursed: Create a 2/2 black Zombie creature token. Activate only as a sorcery.

Doomed Dissenter

When Doomed Dissenter dies, create a 2/2 black Zombie creature token.

Festering Mummy

When Festering Mummy dies, you may put a -1/-1 counter on target creature.

Plague Belcher

Menace
When Plague Belcher enters, put two -1/-1 counters on target creature you control.
Whenever another Zombie you control dies, each opponent loses 1 life.