Yusri, Fortune's Flame

Flying
Whenever Yusri, Fortune's Flame attacks, choose a number between 1 and 5. Flip that many coins. For each flip you win, draw a card. For each flip you lose, Yusri deals 2 damage to you. If you won five flips this way, you may cast spells from your hand this turn without paying their mana costs.

Chain of Vapor

Return target nonland permanent to its owner's hand. Then that permanent's controller may sacrifice a land. If the player does, they may copy this spell and may choose a new target for that copy.

Rite of the Raging Storm

Creatures named Lightning Rager can't attack you or planeswalkers you control.
At the beginning of each player's upkeep, that player creates a 5/1 red Elemental creature token named Lightning Rager. It has trample, haste, and "At the beginning of the end step, sacrifice this creature."

Invert Polarity

Choose target spell, then flip a coin. If you win the flip, gain control of that spell and you may choose new targets for it. If you lose the flip, counter that spell.

Powerbalance

Whenever an opponent casts a spell, you may reveal the top card of your library. If you do, you may cast that card without paying its mana cost if the two spells have the same mana value.

Custody Battle

Enchant creature
Enchanted creature has "At the beginning of your upkeep, target opponent gains control of this creature unless you sacrifice a land."

Polymorphist's Jest

Until end of turn, each creature target player controls loses all abilities and becomes a blue Frog with base power and toughness 1/1.

Mirror of Life Trapping

Whenever a creature enters, if it was cast, exile it, then return all other permanent cards exiled with Mirror of Life Trapping to the battlefield under their owners' control.