Plaguecrafter

When this creature enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.

Joo Dee, One of Many

{B}, {T}: Surveil 1. Create a token that's a copy of this creature, then sacrifice an artifact or creature. Activate only as a sorcery. (To surveil 1, look at the top card of your library. You may put it into your graveyard.)

Accursed Marauder

When this creature enters, each player sacrifices a nontoken creature of their choice.

Grim Haruspex

Morph {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.)
Whenever another nontoken creature you control dies, draw a card.

Victimize

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

Gray Merchant of Asphodel

When this creature enters, 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.)

Skullwinder

Deathtouch
When this creature enters, return target card from your graveyard to your hand, then choose an opponent. That player returns a card from their graveyard to their hand.

Sakura-Tribe Elder

Sacrifice this creature: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Meren of Clan Nel Toth

Whenever another creature you control dies, you get an experience counter.
At the beginning of your end step, choose target creature card in your graveyard. If that card's mana value is less than or equal to the number of experience counters you have, return it to the battlefield. Otherwise, put it into your hand.

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Spore Frog

Sacrifice this creature: Prevent all combat damage that would be dealt this turn.