Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Ravenous Chupacabra

When Ravenous Chupacabra enters, destroy target creature an opponent controls.

Abrupt Decay

This spell can't be countered.
Destroy target nonland permanent with mana value 3 or less.

Shriekmaw

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When Shriekmaw enters, destroy target nonartifact, nonblack creature.
Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Assassin's Trophy

Destroy target permanent an opponent controls. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Vraska, the Silencer

Deathtouch
Whenever a nontoken creature an opponent controls dies, you may pay {1}. If you do, return that card to the battlefield tapped under your control. It's a Treasure artifact with "{T}, Sacrifice this artifact: Add one mana of any color," and it loses all other card types.

Fleshbag Marauder

When Fleshbag Marauder enters, each player sacrifices a creature of their choice.

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

Sol Ring

Dictate of Erebos

Flash
Whenever a creature you control dies, each opponent sacrifices a creature of their choice.