Frogify

Enchant creature
Enchanted creature loses all abilities and is a blue Frog creature with base power and toughness 1/1. (It loses all other card types and creature types.)

Frost Lynx

When this creature enters, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Wishful Merfolk

Defender
{1}{U}: This creature loses defender and becomes a Human until end of turn.

Kasmina, Enigmatic Mentor

Spells your opponents cast that target a creature or planeswalker you control cost {2} more to cast.
−2: Create a 2/2 blue Wizard creature token. Draw a card, then discard a card.

Shoal Serpent

Defender
Landfall — Whenever a land you control enters, this creature loses defender until end of turn.

So Tiny

Flash
Enchant creature
Enchanted creature gets -2/-0. It gets -6/-0 instead as long as its controller has seven or more cards in their graveyard.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Talrand's Invocation

Create two 2/2 blue Drake creature tokens with flying.

Stormtide Leviathan

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
All lands are Islands in addition to their other types.
Creatures without flying or islandwalk can't attack.

Giant Shark

This creature can't attack unless defending player controls an Island.
Whenever this creature blocks or becomes blocked by a creature that has been dealt damage this turn, this creature gets +2/+0 and gains trample until end of turn.
When you control no Islands, sacrifice this creature.

Coral Trickster

Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When this creature is turned face up, you may tap or untap target permanent.

Island

Seascape Aerialist

Whenever this creature or another Ally you control enters, you may have Ally creatures you control gain flying until end of turn.

Aquamorph Entity

As this creature enters or is turned face up, it becomes your choice of 5/1 or 1/5.
Morph {2}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Sphinx's Disciple

Flying
Inspired — Whenever this creature becomes untapped, draw a card.

Amphin Pathmage

{2}{U}: Target creature can't be blocked this turn.

Psychic Rebuttal

Counter target instant or sorcery spell that targets you.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, you may copy the spell countered this way. You may choose new targets for the copy.

Vantress Paladin

Flying
Adamant — If at least three blue mana was spent to cast this spell, this creature enters with a +1/+1 counter on it.

Wind Drake

Will of the Naga

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Tap up to two target creatures. Those creatures don't untap during their controller's next untap step.

Gurmag Drowner

Exploit (When this creature enters, you may sacrifice a creature.)
When this creature exploits a creature, look at the top four cards of your library. Put one of them into your hand and the rest into your graveyard.

Unsummon

Return target creature to its owner's hand.

Jwari Scuttler

Archetype of Imagination

Creatures you control have flying.
Creatures your opponents control lose flying and can't have or gain flying.

Lumengrid Drake

Flying
Metalcraft — When this creature enters, if you control three or more artifacts, return target creature to its owner's hand.

Moat Piranhas

Tome Raider

Flying
When this creature enters, draw a card.

Corridor Monitor

When this creature enters, untap target artifact or creature you control.

Jeskai Runemark

Enchant creature
Enchanted creature gets +2/+2.
Enchanted creature has flying as long as you control a red or white permanent.

Force Away

Return target creature to its owner's hand.
Ferocious — If you control a creature with power 4 or greater, you may draw a card. If you do, discard a card.

Sky Ruin Drake

Thassa's Bounty

Draw three cards. Target player mills three cards.

Azure Drake

Voyage's End

Return target creature to its owner's hand. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Aetherize

Return all attacking creatures to their owner's hand.

Djinn of Wishes

Flying
This creature enters with three wish counters on it.
{2}{U}{U}, Remove a wish counter from this creature: Reveal the top card of your library. You may play that card without paying its mana cost. If you don't, exile it.

Phantasmal Abomination

Defender
When this creature becomes the target of a spell or ability, sacrifice it.

Surrakar Banisher

When this creature enters, you may return target tapped creature to its owner's hand.

Divination

Archaeomancer

When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Whirlwind Adept

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Turn the Tide

Creatures your opponents control get -2/-0 until end of turn.

Snapping Drake

Flying (This creature can't be blocked except by creatures with flying or reach.)

Cloaked Siren

Flash (You may cast this spell any time you could cast an instant.)
Flying

Nullify

Blind Phantasm

Interpret the Signs

Scry 3, then reveal the top card of your library. Draw cards equal to that card's mana value. (To scry 3, look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Sleep

Tap all creatures target player controls. Those creatures don't untap during that player's next untap step.

Talrand, Sky Summoner

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

Man-o'-War

When this creature enters, return target creature to its owner's hand.

Kapsho Kitefins

Flying
Whenever this creature or another creature you control enters, tap target creature an opponent controls.

Rewind

Counter target spell. Untap up to four lands.

Brainstorm

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

Dirgur Nemesis

Defender
Megamorph {6}{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.)

One With the Wind

Enchant creature
Enchanted creature gets +2/+2 and has flying.

Hydrosurge

Target creature gets -5/-0 until end of turn.

Steelgaze Griffin

Flying
Whenever you draw your second card each turn, this creature gets +2/+0 until end of turn.

Cancel

Aerial Guide

Flying
Whenever this creature attacks, another target attacking creature gains flying until end of turn.

Spire Monitor

Peel from Reality

Return target creature you control and target creature you don't control to their owners' hands.

Watercourser

{U}: This creature gets +1/-1 until end of turn.

Ojutai's Breath

Tap target creature. It doesn't untap during its controller's next untap step.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)