Hidden Spider

When an opponent casts a creature spell with flying, if this permanent is an enchantment, it becomes a 3/5 Spider creature with reach. (It can block creatures with flying.)

Spirited Companion

Opal Acrolith

Whenever an opponent casts a creature spell, if this permanent is an enchantment, it becomes a 2/4 Soldier creature.
{0}: This permanent becomes an enchantment.

Serum Visionary

When this creature enters, draw a card, then scry 2.

Gallant Citizen

Priest of Ancient Lore

When this creature enters, you gain 1 life and draw a card.

Mirage Mirror

{2}: This artifact becomes a copy of target artifact, creature, enchantment, or land until end of turn.

Chimeric Egg

Whenever an opponent casts a nonartifact spell, put a charge counter on this artifact.
Remove three charge counters from this artifact: This artifact becomes a 6/6 Construct artifact creature with trample until end of turn.

Veiled Crocodile

When a player has no cards in hand, if this permanent is an enchantment, it becomes a 4/4 Crocodile creature.

Rogue Refiner

When this creature enters, draw a card and you get {E}{E} (two energy counters).

Combat Thresher

Prototype {2}{W} — 1/1 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Double strike
When this creature enters, draw a card.

Hidden Herd

When an opponent plays a nonbasic land, if this permanent is an enchantment, it becomes a 3/3 Beast creature.

Opal Gargoyle

When an opponent casts a creature spell, if this permanent is an enchantment, it becomes a 2/2 Gargoyle creature with flying.

Salt Road Packbeast

This spell costs {1} less to cast for each creature you control.
When this creature enters, draw a card.

Angel's Tomb

Whenever a creature you control enters, you may have this artifact become a 3/3 white Angel artifact creature with flying until end of turn.

Ice-Fang Coatl

Flash
Flying
When this creature enters, draw a card.
This creature has deathtouch as long as you control at least three other snow permanents.

Hidden Ancients

When an opponent casts an enchantment spell, if this permanent is an enchantment, it becomes a 5/5 Treefolk creature.

Fblthp, the Lost

When Fblthp enters, draw a card. If it entered from your library or was cast from your library, draw two cards instead.
When Fblthp becomes the target of a spell, shuffle Fblthp into its owner's library.

Cloudblazer

Flying
When this creature enters, you gain 2 life and draw two cards.

Roving Harper

Opal Guardian

When an opponent casts a creature spell, if this permanent is an enchantment, this enchantment becomes a 3/4 Gargoyle creature with flying and protection from red.

Veiled Serpent

When an opponent casts a spell, if this permanent is an enchantment, it becomes a 4/4 Serpent creature with "This creature can't attack unless defending player controls an Island."
Cycling {2} ({2}, Discard this card: Draw a card.)

Elite Guardmage

Flying
When this creature enters, you gain 3 life and draw a card.

Chronicler of Heroes

When this creature enters, draw a card if you control a creature with a +1/+1 counter on it.

Soul Sculptor

{1}{W}, {T}: Target creature becomes an enchantment and loses all abilities until a player casts a creature spell.

Inspiring Overseer

Flying
When this creature enters, you gain 1 life and draw a card.

Opal Titan

When an opponent casts a creature spell, if this permanent is an enchantment, it becomes a 4/4 Giant creature with protection from each of that spell's colors.

Veil of Birds

When an opponent casts a spell, if this permanent is an enchantment, it becomes a 1/1 Bird creature with flying.

Splash Portal

Exile target creature you control, then return it to the battlefield under its owner's control. If that creature is a Bird, Frog, Otter, or Rat, draw a card.

Beastbond Outcaster

When this creature enters, if you control a creature with power 4 or greater, draw a card.
Plot {1}{G} (You may pay {1}{G} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Veiled Apparition

When an opponent casts a spell, if this permanent is an enchantment, it becomes a 3/3 Illusion creature with flying and "At the beginning of your upkeep, sacrifice this creature unless you pay {1}{U}."

Dreamdew Entrancer

Reach
When this creature enters, tap up to one target creature and put three stun counters on it. If you control that creature, draw two cards.

Lagrella, the Magpie

When Lagrella enters, exile any number of other target creatures controlled by different players until Lagrella leaves the battlefield. When an exiled card enters under your control this way, put two +1/+1 counters on it.

Halcyon Glaze

Whenever you cast a creature spell, this enchantment becomes a 4/4 Illusion creature with flying in addition to its other types until end of turn.

Pond Prophet

Veiled Sentry

When an opponent casts a spell, if this permanent is an enchantment, it becomes an Illusion creature with power and toughness each equal to that spell's mana value.

Momentary Blink

Exile target creature you control, then return it to the battlefield under its owner's control.
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Opal Champion

When an opponent casts a creature spell, if this permanent is an enchantment, it becomes a 3/3 Knight creature with first strike.

Ephemerate

Exile target creature you control, then return it to the battlefield under its owner's control.
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.)

Flicker of Fate

Exile target creature or enchantment, then return it to the battlefield under its owner's control.

Circuit Mender

When this creature enters, you gain 2 life.
When this creature leaves the battlefield, draw a card.

Opal Archangel

When an opponent casts a creature spell, if this permanent is an enchantment, it becomes a 5/5 Angel creature with flying and vigilance.

Chimeric Idol

{0}: Tap all lands you control. This artifact becomes a 3/3 Turtle artifact creature until end of turn.

Hidden Stag

Whenever an opponent plays a land, if this permanent is an enchantment, it becomes a 3/2 Elk Beast creature.
Whenever you play a land, if this permanent is a creature, it becomes an enchantment.

Elvish Visionary

Masked Admirers

When this creature enters, draw a card.
Whenever you cast a creature spell, you may pay {G}{G}. If you do, return this card from your graveyard to your hand.

Clockwork Fox

When this creature leaves the battlefield, you draw two cards and each opponent draws a card.

Mulldrifter

Flying
When this creature enters, draw two cards.
Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Riddleform

Whenever you cast a noncreature spell, you may have this enchantment become a 3/3 Sphinx creature with flying in addition to its other types until end of turn.
{2}{U}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Aether Channeler

When this creature enters, choose one —
• Create a 1/1 white Bird creature token with flying.
• Return another target nonland permanent to its owner's hand.
• Draw a card.

Helpful Hunter

Hidden Guerrillas

When an opponent casts an artifact spell, if this permanent is an enchantment, it becomes a 5/3 Soldier creature with trample.

Duelist's Heritage

Whenever one or more creatures attack, you may have target attacking creature gain double strike until end of turn.

Anticausal Vestige

When this creature leaves the battlefield, draw a card, then you may put a permanent card with mana value less than or equal to the number of lands you control from your hand onto the battlefield tapped.
Warp {4} (You may cast this card from your hand for its warp cost. Exile this creature at the beginning of the next end step, then you may cast it from exile on a later turn.)

Skyscanner

Flying
When this creature enters, draw a card.

Dancing Sword

Equipped creature gets +2/+1.
When equipped creature dies, you may have this Equipment become a 2/1 Construct artifact creature with flying and ward {1}. If you do, it isn't an Equipment.
Equip {1}

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.

Search Party Captain

This spell costs {1} less to cast for each creature you attacked with this turn.
When this creature enters, draw a card.

Pygmy Kavu

When this creature enters, draw a card for each black creature your opponents control.

Llanowar Visionary

When this creature enters, draw a card.
{T}: Add {G}.

Cloudshift

Exile target creature you control, then return that card to the battlefield under your control.

Hidden Predators

When an opponent controls a creature with power 4 or greater, if this permanent is an enchantment, it becomes a 4/4 Beast creature.

Opal Caryatid

When an opponent casts a creature spell, if this permanent is an enchantment, it becomes a 2/2 Soldier creature.