Lord of the Undead

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

Ghoulcaller's Chant

Choose one —
• Return target creature card from your graveyard to your hand.
• Return two target Zombie cards from your graveyard to your hand.

Corpse Harvester

{1}{B}, {T}, Sacrifice a creature: Search your library for a Zombie card and a Swamp card, reveal them, put them into your hand, then shuffle.

Swamp

Lord of the Accursed

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

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters the battlefield, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Calculating Lich

Menace
Whenever a creature attacks one of your opponents, that player loses 1 life.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Death Denied

Return X target creature cards from your graveyard to your hand.

Mortuary Mire

Mortuary Mire enters the battlefield tapped.
When Mortuary Mire enters the battlefield, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.

Stronghold Assassin

{T}, Sacrifice a creature: Destroy target nonblack creature.

Phyrexian Reclamation

{1}{B}, Pay 2 life: Return target creature card from your graveyard to your hand.

Death Baron

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

Undead Warchief

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

Door of Destinies

As Door of Destinies enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.