Cemetery Reaper

Other Zombie creatures you control get +1/+1.
{2}{B}, {T}: Exile target creature card from a graveyard. Create a 2/2 black Zombie creature token.

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Champion of the Perished

Whenever another Zombie you control enters, put a +1/+1 counter on this creature.

Boneknitter

{1}{B}: Regenerate target Zombie.
Morph {2}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Calculating Lich

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

Cursed Minotaur

Menace (This creature can't be blocked except by two or more creatures.)

Corpulent Corpse

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Suspend 5—{B} (Rather than cast this card from your hand, you may pay {B} and exile it with five time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)

Hancock, Ghoulish Mayor

Each other creature you control that's a Zombie or Mutant gets +X/+X, where X is the number of counters on Hancock.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Bog Raiders

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Coffin Queen

You may choose not to untap this creature during your untap step.
{2}{B}, {T}: Put target creature card from a graveyard onto the battlefield under your control. When this creature becomes untapped or you lose control of this creature, exile that creature.

Contagious Nim

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Black Cat

When this creature dies, target opponent discards a card at random.

Butcher Ghoul

Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Three Tree City

As Three Tree City enters, choose a creature type.
{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to the number of creatures you control of the chosen type.