Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Prized Amalgam

Whenever a creature enters, if it entered from your graveyard or you cast it from your graveyard, return Prized Amalgam from your graveyard to the battlefield tapped at the beginning of the next end step.

Tormod, the Desecrator

Whenever one or more cards leave your graveyard, create a tapped 2/2 black Zombie creature token.
Partner (You can have two commanders if both have partner.)

Lord of the Accursed

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

Muldrotha, the Gravetide

During each of your turns, you may play a land and cast a permanent spell of each permanent type from your graveyard. (If a card has multiple permanent types, choose one as you play it.)

Ramunap Excavator

Sidisi, Brood Tyrant

Whenever Sidisi, Brood Tyrant enters or attacks, mill three cards.
Whenever one or more creature cards are put into your graveyard from your library, create a 2/2 black Zombie creature token.

Buried Alive

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

Drown in Filth

Choose target creature. Mill four cards, then that creature gets -1/-1 until end of turn for each land card in your graveyard.