Paragon of Gathering Mists

Other blue creatures you control get +1/+1.
{U}, {T}: Another target blue creature you control gains flying until end of turn.

Neurok Invisimancer

Neurok Invisimancer can't be blocked.
When Neurok Invisimancer enters, target creature can't be blocked this turn.

Youthful Scholar

When Youthful Scholar dies, draw two cards.

Staff of the Mind Magus

Whenever you cast a blue spell or an Island you control enters, you gain 1 life.

Ferropede

Ferropede can't be blocked.
Whenever Ferropede deals combat damage to a player, you may remove a counter from target permanent.

Writ of Passage

Enchant creature
Whenever enchanted creature attacks, if its power is 2 or less, it can't be blocked this turn.
Forecast — {1}{U}, Reveal Writ of Passage from your hand: Target creature with power 2 or less can't be blocked this turn. (Activate only during your upkeep and only once each turn.)

Copper Carapace

Equipped creature gets +2/+2 and can't block.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Tower Geist

Flying
When Tower Geist enters, look at the top two cards of your library. Put one of them into your hand and the other into your graveyard.

Stitcher's Apprentice

{1}{U}, {T}: Create a 2/2 blue Homunculus creature token, then sacrifice a creature.

Phantom Warrior

Opposition

Tap an untapped creature you control: Tap target artifact, creature, or land.

Merfolk Spy

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Merfolk Spy deals combat damage to a player, that player reveals a card at random from their hand.

Illusory Angel

Cast this spell only if you've cast another spell this turn.
Flying

Tricks of the Trade

Enchant creature
Enchanted creature gets +2/+0 and can't be blocked.

Perilous Research

Draw two cards, then sacrifice a permanent.

Homarid Spawning Bed

{1}{U}{U}, Sacrifice a blue creature: Create X 1/1 blue Camarid creature tokens, where X is the sacrificed creature's mana value.

Cloud of Faeries

Flying
When Cloud of Faeries enters, untap up to two lands.
Cycling {2} ({2}, Discard this card: Draw a card.)

Dream Thief

Flying
When Dream Thief enters, draw a card if you've cast another blue spell this turn.

Skywinder Drake

Flying
Skywinder Drake can block only creatures with flying.

Stormbound Geist

Flying
Stormbound Geist can block only creatures with flying.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Surveilling Sprite

Flying
When Surveilling Sprite dies, you may draw a card.

Slip Through Space

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

Soratami Mirror-Guard

Flying
{2}, Return a land you control to its owner's hand: Target creature with power 2 or less can't be blocked this turn.

Perilous Myr

When Perilous Myr dies, it deals 2 damage to any target.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Military Intelligence

Whenever you attack with two or more creatures, draw a card.

Palace Familiar

Flying
When Palace Familiar dies, draw a card.

Moonblade Shinobi

Ninjutsu {2}{U} ({2}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Moonblade Shinobi deals combat damage to a player, create a 1/1 blue Illusion creature token with flying.

Mindshrieker

Flying
{2}: Target player mills a card. Mindshrieker gets +X/+X until end of turn, where X is the milled card's mana value.

Faerie Seer

Spell Syphon

Counter target spell unless its controller pays {1} for each blue permanent you control.

Sage's Row Denizen

Whenever another blue creature you control enters, target player mills two cards.

Vexing Sphinx

Flying
Cumulative upkeep—Discard a card. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
When Vexing Sphinx dies, draw a card for each age counter on it.

Blustersquall

Tap target creature you don't control.
Overload {3}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Cloudfin Raptor

Flying
Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Phyrexian Ironfoot

Phyrexian Ironfoot doesn't untap during your untap step.
{1}{S}: Untap Phyrexian Ironfoot. ({S} can be paid with one mana from a snow source.)

Kapsho Kitefins

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

Brackwater Elemental

When Brackwater Elemental attacks or blocks, sacrifice it at the beginning of the next end step.
Unearth {2}{U} ({2}{U}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Vulshok Morningstar

Equipped creature gets +2/+2.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Invisible Stalker

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

Scroll Thief

Whenever Scroll Thief deals combat damage to a player, draw a card.

Aether Adept

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

Briarberry Cohort

Flying
Briarberry Cohort gets +1/+1 as long as you control another blue creature.

Icebreaker Kraken

This spell costs {1} less to cast for each snow land you control.
When Icebreaker Kraken enters, artifacts and creatures target opponent controls don't untap during that player's next untap step.
Return three snow lands you control to their owner's hand: Return Icebreaker Kraken to its owner's hand.