Demonstrate (When you cast this spell, you may copy it. If you do, choose an opponent to also copy it. Players may choose new targets for their copies.)

Destroy target artifact or creature you don't control. If that permanent is destroyed this way, its controller exiles cards from the top of their library until they exile a nonland card, then they may cast that card without paying its mana cost.

Exile the top three cards of your library. Until the end of your next turn, you may play those cards. If this spell was cast from a graveyard, you may play cards this way without paying their mana costs.

Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Whenever Ryan attacks, exile cards from the top of your library until you exile a nonland card. You may cast the exiled card without paying its mana cost if it's a spell with mana value less than or equal to Ryan's power. Put the exiled cards not cast this way on the bottom of your library in a random order.

Doctor's companion (You can have two commanders if the other is the Doctor.)

Reveal cards from the top of your library until you reveal a nonland card. Put the revealed cards on the bottom of your library in a random order. When you reveal a nonland card this way, Calibrated Blast deals damage equal to that card's mana value to any target.

Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Counter target spell. Choose 1, 2, or 3 at random. Its controller mills that many cards, then exiles cards from the top of their library until they exile a nonland card with a different name than that spell. They may cast that card without paying its mana cost. Then they put the exiled cards on the bottom of their library in a random order.

Gain control of target creature or Vehicle until end of turn. Untap it. It gains haste until end of turn.

You may cast a spell with mana value 2 or less from your hand without paying its mana cost.

For each player, choose target nonenchantment, nonland permanent that player controls. Those permanents' owners shuffle them into their libraries. Each player who controlled one of those permanents exiles cards from the top of their library until they exile a nonland card, then puts the rest on the bottom of their library in a random order. Each player may cast the nonland card they exiled without paying its mana cost.

, : Another target creature you control gains flying and lifelink until end of turn.

At the beginning of your end step, if you gained life this turn, exile cards from the top of your library until you exile a nonland card. You may cast that card without paying its mana cost if the spell's mana value is less than or equal to the amount of life you gained this turn. Otherwise, put it into your hand.

Until end of turn, target blocked creature you control gets +X/+0 and gains trample and "Whenever this creature deals combat damage to a player, look at that many cards from the top of your library. Exile up to one nonland card from among them and put the rest on the bottom of your library in a random order. You may cast the exiled card without paying its mana cost."

Exile the top X cards of your library. You may cast instant and sorcery spells with mana value X or less from among them without paying their mana costs. Then put all cards exiled this way that weren't cast into your graveyard.

Exile target creature an opponent controls. That player reveals cards from their sideboard at random until they reveal a nonland card. They may cast that card without paying its mana cost.

If an opponent controls an Island and you control a Mountain, you may cast this spell without paying its mana cost.

Destroy target artifact.

You may exile a red card with mana value X from your hand rather than pay this spell's mana cost.

Target creature gets +X/+0 until end of turn.

You may sacrifice a Mountain rather than pay this spell's mana cost.

Target creature gets +X/+0 until end of turn, where X is the number of Mountains you control.

Exile the top six cards of your library. You may cast up to two sorcery spells with mana value 3 or less from among them without paying their mana costs. Put the exiled cards not cast this way on the bottom of your library in a random order.

, Discard a card: Draw a card.

, : Reveal cards from the top of your library until you reveal a nonlegendary, nonland card with mana value 3 or less. You may cast that card without paying its mana cost. Put all revealed cards not cast this way on the bottom of your library in a random order.

If it's not your turn, you may exile a red card from your hand rather than pay this spell's mana cost.

Create two 3/1 red Elemental creature tokens with trample and haste. Sacrifice those tokens at the beginning of your next upkeep.

Electrodominance deals X damage to any target. You may cast a spell with mana value X or less from your hand without paying its mana cost.