Leyline of Anticipation

If this card is in your opening hand, you may begin the game with it on the battlefield.
You may cast spells as though they had flash.

God-Eternal Kefnet

Flying
You may reveal the first card you draw each turn as you draw it. Whenever you reveal an instant or sorcery card this way, copy that card and you may cast the copy. That copy costs {2} less to cast.
When God-Eternal Kefnet dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

High Fae Trickster

Flash (You may cast this spell any time you could cast an instant.)
Flying
You may cast spells as though they had flash.

Tidal Barracuda

Any player may cast spells as though they had flash.
Your opponents can't cast spells during your turn.

Orvar, the All-Form

Changeling
Whenever you cast an instant or sorcery spell, if it targets one or more other permanents you control, create a token that's a copy of one of those permanents.
When a spell or ability an opponent controls causes you to discard this card, create a token that's a copy of target permanent.

Wash Away

Cleave {1}{U}{U} (You may cast this spell for its cleave cost. If you do, remove the words in square brackets.)
Counter target spell [that wasn't cast from its owner's hand].

Geyser Drake

Flying
During turns other than yours, spells you cast cost {1} less to cast.

Glen Elendra Pranksters

Flying
Whenever you cast a spell during an opponent's turn, you may return target creature you control to its owner's hand.

Murmuring Mystic

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Naiad of Hidden Coves

During turns other than yours, spells you cast cost {1} less to cast.

Abjure

As an additional cost to cast this spell, sacrifice a blue permanent.
Counter target spell.

Brineborn Cutthroat

Flash (You may cast this spell any time you could cast an instant.)
Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on this creature.

Wavebreak Hippocamp

Whenever you cast your first spell during each opponent's turn, draw a card.

Aminatou's Augury

Exile the top eight cards of your library. You may put a land card from among them onto the battlefield. Until end of turn, for each nonland card type, you may cast a spell of that type from among the exiled cards without paying its mana cost.

Alandra, Sky Dreamer

Whenever you draw your second card each turn, create a 2/2 blue Drake creature token with flying.
Whenever you draw your fifth card each turn, Alandra and Drakes you control each get +X/+X until end of turn, where X is the number of cards in your hand.

Teferi's Ageless Insight

If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.

Reset

Cast this spell only during an opponent's turn after their upkeep step.
Untap all lands you control.

Gandalf, Friend of the Shire

Flash
You may cast sorcery spells as though they had flash.
Whenever the Ring tempts you, if you chose a creature other than Gandalf as your Ring-bearer, draw a card.

Shackle Slinger

Whenever you cast your second spell each turn, choose target creature an opponent controls. If it's tapped, put a stun counter on it. Otherwise, tap it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Counterspell

Mind's Dilation

Whenever an opponent casts their first spell each turn, that player exiles the top card of their library. If it's a nonland card, you may cast it without paying its mana cost.

Deem Inferior

This spell costs {1} less to cast for each card you've drawn this turn.
The owner of target nonland permanent puts it into their library second from the top or on the bottom.

Jin-Gitaxias, Core Augur

Flash
At the beginning of your end step, draw seven cards.
Each opponent's maximum hand size is reduced by seven.

As Foretold

At the beginning of your upkeep, put a time counter on this enchantment.
Once each turn, you may pay {0} rather than pay the mana cost for a spell you cast with mana value X or less, where X is the number of time counters on this enchantment.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.