Blighted Agent

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Blighted Agent can't be blocked.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Fierce Guardianship

If you control a commander, you may cast this spell without paying its mana cost.
Counter target noncreature spell.

Resculpt

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Serum Visions

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Miscast

Counter target instant or sorcery spell unless its controller pays {3}.

Foil

You may discard an Island card and another card rather than pay this spell's mana cost.
Counter target spell.

Nadir Kraken

Whenever you draw a card, you may pay {1}. If you do, put a +1/+1 counter on Nadir Kraken and create a 1/1 blue Tentacle creature token.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Careful Study

Counterspell

Leap

Target creature gains flying until end of turn.
Draw a card.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Deekah, Fractal Theorist

Magecraft — Whenever you cast or copy an instant or sorcery spell, create a 0/0 green and blue Fractal creature token. Put X +1/+1 counters on it, where X is that spell's mana value.
{3}{U}: Target creature token can't be blocked this turn.

Narset's Reversal

Copy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.

Pact of Negation

Counter target spell.
At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Triton Shorestalker

Final Iteration

Flying
Wizards you control get +2/+1 and have flying.
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token.

Docent of Perfection

Flying
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token. Then if you control three or more Wizards, transform Docent of Perfection.

Docent of Perfection // Final Iteration

Faerie Seer

Flying
When Faerie Seer enters, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Disdainful Stroke

Counter target spell with mana value 4 or greater.

Mental Misstep

({U/P} can be paid with either {U} or 2 life.)
Counter target spell with mana value 1.

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.

Stubborn Denial

Counter target noncreature spell unless its controller pays {1}.
Ferocious — If you control a creature with power 4 or greater, counter that spell instead.

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Spectral Sailor

Flash (You may cast this spell any time you could cast an instant.)
Flying
{3}{U}: Draw a card.

Slip Through Space

Devoid (This card has no color.)
Target creature can't be blocked this turn.
Draw a card.

Curate

Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Draw a card.

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

Octavia, Living Thesis

This spell costs {8} less to cast if you have eight or more instant and/or sorcery cards in your graveyard.
Ward {8}
Magecraft — Whenever you cast or copy an instant or sorcery spell, target creature has base power and toughness 8/8 until end of turn.

Looter il-Kor

Shadow (This creature can block or be blocked by only creatures with shadow.)
Whenever Looter il-Kor deals damage to an opponent, draw a card, then discard a card.

Mana Leak

Counter target spell unless its controller pays {3}.

Mana Drain

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

Gudul Lurker

Gudul Lurker can't be blocked.
Megamorph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Wonder

Flying
As long as Wonder is in your graveyard and you control an Island, creatures you control have flying.

Mental Note

Murmuring Mystic

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

Pteramander

Flying
{7}{U}: Adapt 4. This ability costs {1} less to activate for each instant and sorcery card in your graveyard. (If this creature has no +1/+1 counters on it, put four +1/+1 counters on it.)

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Mist-Cloaked Herald

Shadow Rift

Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)
Draw a card.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Venture Deeper

Target player mills four cards. (Then exile this card. You may cast the creature later from exile.)

Merfolk Secretkeeper

Merfolk Secretkeeper // Venture Deeper

Unwind

Counter target noncreature spell. Untap up to three lands.

Negate

Slither Blade

Invisible Stalker

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Invisible Stalker can't be blocked.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.