Salt Road Ambushers

Whenever another permanent you control is turned face up, if it's a creature, put two +1/+1 counters on it.
Megamorph {3}{G}{G} (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.)

Krosan Cloudscraper

At the beginning of your upkeep, sacrifice this creature unless you pay {G}{G}.
Morph {7}{G}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Murder

Basilica Stalker

Flying
Whenever this creature deals combat damage to a player, you gain 1 life and surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Disguise {4}{B} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

Supernatural Stamina

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Branch of Vitu-Ghazi

{T}: Add {C}.
Disguise {3} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
When this land is turned face up, add two mana of any one color. Until end of turn, you don't lose this mana as steps and phases end.

Zimone's Hypothesis

You may put a +1/+1 counter on a creature. Then choose odd or even. Return each creature with power of the chosen quality to its owner's hand. (Zero is even.)

Creeping Peeper

{T}: Add {U}. Spend this mana only to cast an enchantment spell, unlock a door, or turn a permanent face up.

Abomination of Gudul

Flying
Whenever this creature deals combat damage to a player, you may draw a card. If you do, discard a card.
Morph {2}{B}{G}{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.)

Silumgar's Command

Choose two —
• Counter target noncreature spell.
• Return target permanent to its owner's hand.
• Target creature gets -3/-3 until end of turn.
• Destroy target planeswalker.

Bubble Smuggler

Disguise {5}{U} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
As this creature is turned face up, put four +1/+1 counters on it.

Hunted Bonebrute

Menace
When this creature enters, target opponent creates two 1/1 white Dog creature tokens.
When this creature dies, each opponent loses 3 life.
Disguise {1}{B}

Honest Rutstein

When Honest Rutstein enters, return target creature card from your graveyard to your hand.
Creature spells you cast cost {1} less to cast.

Nervous Gardener

Disguise {G} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
When this creature is turned face up, search your library for a land card with a basic land type, reveal it, put it into your hand, then shuffle.

They Went This Way

Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Brine Elemental

Morph {5}{U}{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, each opponent skips their next untap step.

Lumbering Laundry

{2}: Until end of turn, you may look at face-down creatures you don't control any time.
Disguise {5} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

Kasmina's Transmutation

Enchant creature
Enchanted creature loses all abilities and has base power and toughness 1/1.

Unlikely Aid

Target creature gets +2/+0 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Map the Frontier

Search your library for up to two basic land cards and/or Desert cards, put them onto the battlefield tapped, then shuffle.

Whisperwood Elemental

At the beginning of your end step, manifest the top card of your library. (Put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)
Sacrifice this creature: Until end of turn, face-up nontoken creatures you control gain "When this creature dies, manifest the top card of your library."

Thousand Winds

Flying
Morph {5}{U}{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, return all other tapped creatures to their owners' hands.

Faerie Snoop

Flying
Disguise {1}{U/B}{U/B} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
When this creature is turned face up, look at the top two cards of your library. Put one into your hand and the other into your graveyard.

Sultai Runemark

Enchant creature
Enchanted creature gets +2/+2.
Enchanted creature has deathtouch as long as you control a green or blue permanent. (Any amount of damage it deals to a creature is enough to destroy it.)

Weaver of Lies

Morph {4}{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, turn any number of target creatures with morph abilities other than this creature face down.

Revealing Wind

Prevent all combat damage that would be dealt this turn. You may look at each face-down creature that's attacking or blocking.

Ghastly Conscription

Exile all creature cards from target player's graveyard in a face-down pile, shuffle that pile, then manifest those cards. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Kadena's Silencer

When this creature is turned face up, counter all abilities your opponents control.
Megamorph {1}{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.)

Monstrous Emergence

As an additional cost to cast this spell, choose a creature you control or reveal a creature card from your hand.
Monstrous Emergence deals damage equal to the power of the creature you chose or the card you revealed to target creature.

Vesuvan Shapeshifter

As this creature enters or is turned face up, you may choose another creature on the battlefield. If you do, until this creature is turned face down, it becomes a copy of that creature, except it has "At the beginning of your upkeep, you may turn this creature face down."
Morph {1}{U}

Deathmist Raptor

Deathtouch
Whenever a permanent you control is turned face up, you may return this card from your graveyard to the battlefield face up or face down.
Megamorph {4}{G} (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.)

Ainok Survivalist

Megamorph {1}{G} (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.)
When this creature is turned face up, destroy target artifact or enchantment an opponent controls.

Swamp

Finale of Eternity

Destroy up to three target creatures with toughness X or less. If X is 10 or more, return all creature cards from your graveyard to the battlefield.

Alley Assailant

This creature enters tapped.
Disguise {4}{B}{B} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
When this creature is turned face up, target opponent loses 3 life and you gain 3 life.

Undercover Crocodelf

Whenever this creature deals combat damage to a player, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Disguise {3}{G/U}{G/U} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

Lens of Clarity

You may look at the top card of your library and at face-down creatures you don't control any time.

Dream Chisel

Face-down creature spells you cast cost {1} less to cast.

Wildcall

Manifest the top card of your library, then put X +1/+1 counters on it. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Culvert Ambusher

When this creature enters or is turned face up, target creature blocks this turn if able.
Disguise {4}{G} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)

Ruthless Ripper

Deathtouch
Morph—Reveal a black card in your hand. (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, target player loses 2 life.

Spark Harvest

As an additional cost to cast this spell, sacrifice a creature or pay {3}{B}.
Destroy target creature or planeswalker.

Yedora, Grave Gardener

Whenever another nontoken creature you control dies, you may return it to the battlefield face down under its owner's control. It's a Forest land. (It has no other types or abilities.)

Crack Open

Destroy target artifact or enchantment. Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Greenbelt Radical

Disguise {5}{G}{G} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
When this creature is turned face up, put a +1/+1 counter on each creature you control. Creatures you control gain trample until end of turn.

Trail of Mystery

Whenever a face-down creature you control enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Whenever a permanent you control is turned face up, if it's a creature, it gets +2/+2 until end of turn.

Island

Unauthorized Exit

Return target nonland permanent to its owner's hand. Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Deduce

Draw a card. Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Chromeshell Crab

Morph {4}{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 exchange control of target creature you control and target creature an opponent controls.

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.)

Staggering Size

Target creature gets +3/+3 and gains trample until end of turn.

Defiant Survivor

Survival — At the beginning of your second main phase, if this creature is tapped, manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

Kadena, Slinking Sorcerer

The first face-down creature spell you cast each turn costs {3} less to cast.
Whenever a face-down creature you control enters, draw a card.

Foreboding Landscape

{T}: Add {C}.
{T}, Sacrifice this land: Search your library for a basic Swamp, Forest, or Island card, put it onto the battlefield tapped, then shuffle.
Cycling {B}{G}{U} ({B}{G}{U}, Discard this card: Draw a card.)

Pine Walker

Morph {4}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
Whenever this creature or another creature you control is turned face up, untap that creature.

Vengeful Creeper

Disguise {5}{G} (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
When this creature is turned face up, destroy target artifact or enchantment an opponent controls.

Silumgar Spell-Eater

Megamorph {4}{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.)
When this creature is turned face up, counter target spell unless its controller pays {3}.

Take the Fall

Target creature gets -1/-0 until end of turn. It gets -4/-0 until end of turn instead if you control an outlaw. (Assassins, Mercenaries, Pirates, Rogues, and Warlocks are outlaws.)
Draw a card.

Dramatic Accusation

Enchant creature
When this Aura enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.
{U}{U}: Shuffle enchanted creature into its owner's library.

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.)

Mirage Mesa

This land enters tapped. As it enters, choose a color.
{T}: Add one mana of the chosen color.

Gift of Doom

Enchant creature
Enchanted creature has deathtouch and indestructible.
Morph—Sacrifice another creature. (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
As this Aura is turned face up, you may attach it to a creature.

Ojutai Interceptor

Flying
Megamorph {3}{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.)

Experimental Augury

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. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Projektor Inspector

Whenever this creature or another Detective you control enters and whenever a Detective you control is turned face up, you may draw a card. If you do, discard a card.

Forest

Return to Action

Until end of turn, target creature gets +1/+0 and gains lifelink and "When this creature dies, return it to the battlefield tapped under its owner's control."

Mystic of the Hidden Way

This creature can't be blocked.
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.)

Obscuring Aether

Face-down creature spells you cast cost {1} less to cast.
{1}{G}: Turn this enchantment face down. (It becomes a 2/2 creature.)

Bane of the Living

Morph {X}{B}{B} (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, all creatures get -X/-X until end of turn.