Witness of Tomorrows

Youthful Valkyrie

Flying
Whenever another Angel enters the battlefield under your control, put a +1/+1 counter on Youthful Valkyrie.

Eidolon of Philosophy

{6}{U}, Sacrifice Eidolon of Philosophy: Draw three cards.

Temple of Enlightenment

Temple of Enlightenment enters the battlefield tapped.
When Temple of Enlightenment enters the battlefield, scry 1.
{T}: Add {W} or {U}.

Basri's Solidarity

Put a +1/+1 counter on each creature you control.

Transcendent Envoy

Flying
Aura spells you cast cost {1} less to cast.

Legion's Judgment

Destroy target creature with power 4 or greater.

Traveler's Amulet

{1}, Sacrifice Traveler's Amulet: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Thryx, the Sudden Storm

Flash
Flying
Spells you cast with mana value 5 or greater cost {1} less to cast and can't be countered.

Gates of Istfell

Gates of Istfell enters the battlefield tapped.
{T}: Add {W}.
{2}{W}{U}{U}, {T}, Sacrifice Gates of Istfell: You gain 2 life and draw two cards.

Thassa's Oracle

When Thassa's Oracle enters the battlefield, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Cave of the Frost Dragon

If you control two or more other lands, Cave of the Frost Dragon enters the battlefield tapped.
{T}: Add {W}.
{4}{W}: Cave of the Frost Dragon becomes a 3/4 white Dragon creature with flying until end of turn. It's still a land.

Minimus Containment

Enchant nonland permanent
Enchanted permanent is a Treasure artifact with "{T}, Sacrifice this artifact: Add one mana of any color," and it loses all other abilities. (If it was a creature, it's no longer a creature.)

Deny the Divine

Counter target creature or enchantment spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Wings of Hubris

Equipped creature has flying.
Sacrifice Wings of Hubris: Equipped creature can't be blocked this turn. Sacrifice it at the beginning of the next end step.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Glacial Floodplain

({T}: Add {W} or {U}.)
Glacial Floodplain enters the battlefield tapped.

Thaumaturge's Familiar

Flying
When Thaumaturge's Familiar enters the battlefield, scry 1.

Meandering River

Meandering River enters the battlefield tapped.
{T}: Add {W} or {U}.

Air-Cult Elemental

Flying
Whirlwind — When Air-Cult Elemental enters the battlefield, return up to one other target creature to its owner's hand.

Replicating Ring

{T}: Add one mana of any color.
At the beginning of your upkeep, put a night counter on Replicating Ring. Then if it has eight or more night counters on it, remove all of them and create eight colorless snow artifact tokens named Replicated Ring with "{T}: Add one mana of any color."

You're Ambushed on the Road

Choose one —
• Make a Retreat — Return target creature you control to its owner's hand.
• Stand and Fight — Target creature gets +1/+3 until end of turn.

Omen of the Sea

Flash
When Omen of the Sea enters the battlefield, scry 2, then draw a card.
{2}{U}, Sacrifice Omen of the Sea: Scry 2.

White Dragon

Flying
Cold Breath — When White Dragon enters the battlefield, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Amorphous Axe

Equipped creature gets +3/+0 and is every creature type.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Ichthyomorphosis

Enchant creature
Enchanted creature loses all abilities and is a blue Fish with base power and toughness 0/1.

Disdainful Stroke

Counter target spell with mana value 4 or greater.

Doomskar

Destroy all creatures.
Foretell {1}{W}{W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Entrancing Lyre

You may choose not to untap Entrancing Lyre during your untap step.
{X}, {T}: Tap target creature with power X or less. It doesn't untap during its controller's untap step for as long as Entrancing Lyre remains tapped.

Blue Dragon

Flying
Lightning Breath — When Blue Dragon enters the battlefield, until your next turn, target creature an opponent controls gets -3/-0, up to one other target creature gets -2/-0, and up to one other target creature gets -1/-0.

Warden of Evos Isle

Flying
Creature spells with flying you cast cost {1} less to cast.

Unknown Shores

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Soul of the Rapids

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

Ranger's Hawk

Flying
{3}, {T}, Tap another untapped creature you control: Venture into the dungeon. Activate only as a sorcery. (Enter the first room or advance to the next room.)

Plains

Heliod's Intervention

Choose one —
• Destroy X target artifacts and/or enchantments.
• Target player gains twice X life.

You Hear Something on Watch

Choose one —
• Rouse the Party — Creatures you control get +1/+1 until end of turn.
• Set Off Traps — This spell deals 5 damage to target attacking creature.

Karametra's Blessing

Target creature gets +2/+2 until end of turn. If it's an enchanted creature or enchantment creature, it also gains hexproof and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Stalwart Valkyrie

You may pay {1}{W} and exile a creature card from your graveyard rather than pay this spell's mana cost.
Flying

Sage of the Beyond

Flying
Spells you cast from anywhere other than your hand cost {2} less to cast.
Foretell {4}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Revoke Existence

Bound in Gold

Enchant permanent
Enchanted permanent can't attack, block, or crew Vehicles, and its activated abilities can't be activated unless they're mana abilities.

Glimpse the Cosmos

Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.
As long as you control a Giant, you may cast Glimpse the Cosmos from your graveyard by paying {U} rather than paying its mana cost. If you cast Glimpse the Cosmos this way and it would be put into your graveyard, exile it instead.

Altar of the Pantheon

Your devotion to each color and each combination of colors is increased by one.
{T}: Add one mana of any color. If you control a God, a Demigod, or a legendary enchantment, you gain 1 life.

Staggering Insight

Enchant creature
Enchanted creature gets +1/+1 and has lifelink and "Whenever this creature deals combat damage to a player, draw a card."

Stern Dismissal

Return target creature or enchantment an opponent controls to its owner's hand.

Spectral Steel

Enchant creature
Enchanted creature gets +2/+2.
{1}{W}, Exile Spectral Steel from your graveyard: Return another target Aura or Equipment card from your graveyard to your hand.

Threnody Singer

Flash
Flying
When Threnody Singer enters the battlefield, target creature an opponent controls gets -X/-0 until end of turn, where X is your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Arborea Pegasus

Flying
When Arborea Pegasus enters the battlefield, target creature gets +1/+1 and gains flying until end of turn.

Alrund's Epiphany

Create two 1/1 blue Bird creature tokens with flying. Take an extra turn after this one. Exile Alrund's Epiphany.
Foretell {4}{U}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Shepherd of the Cosmos

Flying
When Shepherd of the Cosmos enters the battlefield, return target permanent card with mana value 2 or less from your graveyard to the battlefield.
Foretell {3}{W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Memory Drain

Island

Daybreak Chimera

This spell costs {X} less to cast, where X is your devotion to white. (Each {W} in the mana costs of permanents you control counts toward your devotion to white.)
Flying

Dream Trawler

Flying, lifelink
Whenever you draw a card, Dream Trawler gets +1/+0 until end of turn.
Whenever Dream Trawler attacks, draw a card.
Discard a card: Dream Trawler gains hexproof until end of turn. Tap it.

Invoke the Divine

Destroy target artifact or enchantment. You gain 4 life.

Riot Control

You gain 1 life for each creature your opponents control. Prevent all damage that would be dealt to you this turn.

Glimpse of Freedom

Draw a card.
Escape—{2}{U}, Exile five other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

Silver Raven

Flying
When Silver Raven enters the battlefield, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Iron Verdict

Iron Verdict deals 5 damage to target tapped creature.
Foretell {W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Clear the Mind

Target player shuffles their graveyard into their library.
Draw a card.

Azorius Locket

{T}: Add {W} or {U}.
{W/U}{W/U}{W/U}{W/U}, {T}, Sacrifice Azorius Locket: Draw two cards.

Sentinel's Eyes

Enchant creature
Enchanted creature gets +1/+1 and has vigilance.
Escape—{W}, Exile two other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

Archon of Falling Stars

Flying
When Archon of Falling Stars dies, you may return target enchantment card from your graveyard to the battlefield.

Hieroglyphic Illumination

Draw two cards.
Cycling {U} ({U}, Discard this card: Draw a card.)

Pentarch Ward

Enchant creature
As Pentarch Ward enters the battlefield, choose a color.
When Pentarch Ward enters the battlefield, draw a card.
Enchanted creature has protection from the chosen color. This effect doesn't remove Pentarch Ward.

Callaphe, Beloved of the Sea

Callaphe's power is equal to your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)
Creatures and enchantments you control have "Spells your opponents cast that target this permanent cost {1} more to cast."

Angel of the Dawn

Flying
When Angel of the Dawn enters the battlefield, creatures you control get +1/+1 and gain vigilance until end of turn.

Divination

Ascended Lawmage

Wind Drake

Revitalize

Kangee, Sky Warden

Flying, vigilance
Whenever Kangee, Sky Warden attacks, attacking creatures with flying get +2/+0 until end of turn.
Whenever Kangee blocks, blocking creatures with flying get +0/+2 until end of turn.