Reverse the Sands

Redistribute any number of players' life totals. (Each of those players gets one life total back.)

Juri, Master of the Revue

Whenever you sacrifice a permanent, put a +1/+1 counter on Juri.
When Juri dies, it deals damage equal to its power to any target.

Gleaming Geardrake

Flying
When this creature enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Whenever you sacrifice an artifact, put a +1/+1 counter on this creature.

Reckless Fireweaver

Whenever an artifact you control enters, this creature deals 1 damage to each opponent.

Mayhem Devil

Whenever a player sacrifices a permanent, this creature deals 1 damage to any target.

Breya's Apprentice

When this creature enters, create a 1/1 colorless Thopter artifact creature token with flying.
{T}, Sacrifice an artifact: Choose one —
• Exile the top card of your library. Until the end of your next turn, you may play that card.
• Target creature gets +2/+0 until end of turn.

Experimental Confectioner

When this creature enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
Whenever you sacrifice a Food, create a 1/1 black Rat creature token with "This token can't block."

Breya, Etherium Shaper

When Breya enters, create two 1/1 blue Thopter artifact creature tokens with flying.
{2}, Sacrifice two artifacts: Choose one —
• Breya deals 3 damage to target player or planeswalker.
• Target creature gets -4/-4 until end of turn.
• You gain 5 life.

Heartstone

Activated abilities of creatures cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.