Pitiless Plunderer

Whenever another creature you control dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Stitched Assistant

Exploit (When this creature enters, you may sacrifice a creature.)
When Stitched Assistant exploits a creature, scry 1, then draw a card. (To scry 1, look at the top card of your library, then you may put that card on the bottom.)

Chatterfang, Squirrel General

Forestwalk (This creature can't be blocked as long as defending player controls a Forest.)
If one or more tokens would be created under your control, those tokens plus that many 1/1 green Squirrel creature tokens are created instead.
{B}, Sacrifice X Squirrels: Target creature gets +X/-X until end of turn.

Chitterspitter

At the beginning of your upkeep, you may sacrifice a token. If you do, put an acorn counter on Chitterspitter.
Squirrels you control get +1/+1 for each acorn counter on Chitterspitter.
{G}, {T}: Create a 1/1 green Squirrel creature token.

Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.

Naban, Dean of Iteration

If a Wizard you control entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Phantasmal Image

You may have Phantasmal Image enter as a copy of any creature on the battlefield, except it's an Illusion in addition to its other types and it has "When this creature becomes the target of a spell or ability, sacrifice it."

Profaner of the Dead

Exploit (When this creature enters, you may sacrifice a creature.)
When Profaner of the Dead exploits a creature, return to their owners' hands all creatures your opponents control with toughness less than the exploited creature's toughness.

Silumgar Sorcerer

Flash (You may cast this spell any time you could cast an instant.)
Flying
Exploit (When this creature enters, you may sacrifice a creature.)
When Silumgar Sorcerer exploits a creature, counter target creature spell.

Vulturous Aven

Flying
Exploit (When this creature enters, you may sacrifice a creature.)
When Vulturous Aven exploits a creature, you draw two cards and you lose 2 life.

Overcharged Amalgam

Flash
Flying
Exploit (When this creature enters, you may sacrifice a creature.)
When Overcharged Amalgam exploits a creature, counter target spell, activated ability, or triggered ability.

Dread Whispers

You draw a card and you lose 1 life. (Then exile this card. You may cast the creature later from exile.)

Mosswood Dreadknight

Trample
When Mosswood Dreadknight dies, you may cast it from your graveyard as an Adventure until the end of your next turn.

Mosswood Dreadknight // Dread Whispers

Skull Skaab

Exploit (When this creature enters, you may sacrifice a creature.)
Whenever a creature you control exploits a nontoken creature, create a 2/2 black Zombie creature token.

Sidisi, Undead Vizier

Deathtouch
Exploit (When this creature enters, you may sacrifice a creature.)
When Sidisi, Undead Vizier exploits a creature, you may search your library for a card, put it into your hand, then shuffle.

Endurance

Flash
Reach
When Endurance enters, up to one target player puts all the cards from their graveyard on the bottom of their library in a random order.
Evoke—Exile a green card from your hand.

Petty Theft

Return target nonland permanent an opponent controls to its owner's hand.

Brazen Borrower

Flash
Flying
Brazen Borrower can block only creatures with flying.

Brazen Borrower // Petty Theft

Fell Stinger

Deathtouch
Exploit (When this creature enters, you may sacrifice a creature.)
When Fell Stinger exploits a creature, target player draws two cards and loses 2 life.

Repository Skaab

Exploit (When this creature enters, you may sacrifice a creature.)
When Repository Skaab exploits a creature, return target instant or sorcery card from your graveyard to your hand.

Henry Wu, InGen Geneticist

Henry Wu, InGen Geneticist and other Human creatures you control have exploit. (When a creature with exploit enters, you may sacrifice a creature.)
Whenever a creature you control exploits a non-Human creature, draw a card. If the exploited creature had power 3 or greater, create a Treasure token.