Master of Pearls

Morph {3}{W}{W} (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 Master of Pearls is turned face up, creatures you control get +2/+2 until end of turn.

Panoptic Projektor

{T}: The next face-down creature spell you cast this turn costs {3} less to cast.
If turning a face-down permanent face up causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Ransom Note

When Ransom Note enters, surveil 1.
{2}, Sacrifice Ransom Note: Choose one —
• Cloak the top card of your library.
• Goad target creature.
• Draw a card.

Crowd-Control Warden

As Crowd-Control Warden enters or is turned face up, put X +1/+1 counters on it, where X is the number of other creatures you control.
Disguise {3}{G/W}{G/W} (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.)

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 Nervous Gardener 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.

Forest

Sol Ring

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

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 Greenbelt Radical is turned face up, put a +1/+1 counter on each creature you control. Creatures you control gain trample until end of turn.

Plains

Showstopping Surprise

Choose target creature you control. Turn it face up if it's face down. Then it deals damage equal to its power to each other creature.

Fortune Thief

Damage that would reduce your life total to less than 1 reduces it to 1 instead.
Morph {R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Neighborhood Guardian

Whenever another creature you control with power 2 or less enters, target creature you control gets +1/+1 until end of turn.

Worldsoul's Rage

Worldsoul's Rage deals X damage to any target. Put up to X land cards from your hand and/or graveyard onto the battlefield tapped.

Tunnel Tipster

At the beginning of your end step, if a face-down creature entered the battlefield under your control this turn, put a +1/+1 counter on Tunnel Tipster.
{T}: Add {G}.

Pyrotechnic Performer

Disguise {R} (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.)
Whenever Pyrotechnic Performer or another creature you control is turned face up, that creature deals damage equal to its power to each opponent.

Goblin Maskmaker

Whenever Goblin Maskmaker attacks, face-down spells you cast this turn cost {1} less to cast.

Yarus, Roar of the Old Gods

Other creatures you control have haste.
Whenever one or more face-down creatures you control deal combat damage to a player, draw a card.
Whenever a face-down creature you control dies, return it to the battlefield face down under its owner's control if it's a permanent card, then turn it face up.

Experiment Twelve

Trample
Whenever Experiment Twelve or another creature you control is turned face up, put +1/+1 counters on that creature equal to its power.
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.)

Buried in the Garden

Enchant land
When Buried in the Garden enters, exile target nonland permanent you don't control until Buried in the Garden leaves the battlefield.
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

Veiled Ascension

When Veiled Ascension enters, put a flying counter on each face-down creature you control.
Face-down creatures you control enter with a flying counter on them.
At the beginning of your upkeep, you may cloak the top card of your library.

Havoc Eater

Flying
When Havoc Eater enters, for each opponent, goad up to one target creature that opponent controls. Put X +1/+1 counters on Havoc Eater, where X is the total power of creatures goaded this way.

True Identity

Whenever True Identity or another permanent you control is turned face up, scry 1, then draw a card. This ability triggers only once each turn.
Disguise {W} (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.)

Sumala Rumblers

Sumala Rumblers's power is equal to the number of creatures you control.
Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Sumala Sentry

Reach
Whenever a face-down permanent you control is turned face up, put a +1/+1 counter on it and a +1/+1 counter on Sumala Sentry.

Primal Whisperer

Primal Whisperer gets +2/+2 for each face-down creature on the battlefield.
Morph {3}{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.)

Mountain

Printlifter Ooze

Deathtouch
Whenever Printlifter Ooze or another creature you control is turned face up, create a 0/0 green Ooze creature token with trample. The token enters with X +1/+1 counters on it, where X is the number of other creatures you control.
Disguise {3}{G}

Brash Taunter

Indestructible
Whenever Brash Taunter is dealt damage, it deals that much damage to target opponent.
{2}{R}, {T}: Brash Taunter fights another target creature.

Trouble in Pairs

If an opponent would begin an extra turn, that player skips that turn instead.
Whenever an opponent attacks you with two or more creatures, draws their second card each turn, or casts their second spell each turn, you draw a card.

Hide in Plain Sight

Look at the top five cards of your library, cloak two of them, and put the rest on the bottom of your library in a random order. (To cloak a card, put it onto the battlefield face down as a 2/2 creature with ward {2}. Turn it face up any time for its mana cost if it's a creature card.)

Hidden Dragonslayer

Lifelink
Megamorph {2}{W} (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 Hidden Dragonslayer is turned face up, destroy target creature with power 4 or greater an opponent controls.

Warleader's Call

Creatures you control get +1/+1.
Whenever a creature you control enters, Warleader's Call deals 1 damage to each opponent.

Anzrag, the Quake-Mole

Whenever Anzrag, the Quake-Mole becomes blocked, untap each creature you control. After this phase, there is an additional combat phase.
{3}{R}{R}{G}{G}: Anzrag must be blocked each combat this turn if able.

Case of the Trampled Garden

When this Case enters, distribute two +1/+1 counters among one or two target creatures you control.
To solve — Creatures you control have total power 8 or greater. (If unsolved, solve at the beginning of your end step.)
Solved — Whenever you attack, put a +1/+1 counter on target attacking creature. It gains trample until end of turn.

Duskana, the Rage Mother

When Duskana, the Rage Mother enters, draw a card for each creature you control with base power and toughness 2/2.
Whenever a creature you control with base power and toughness 2/2 attacks, it gets +3/+3 until end of turn.

Bolrac-Clan Basher

Double strike, trample
Disguise {3}{R}{R} (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.)

Kaust, Eyes of the Glade

Whenever a creature you control that was turned face up this turn deals combat damage to a player, draw a card.
{T}: Turn target face-down attacking creature you control face up.

Arcane Signet

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.