Conundrum Sphinx

Flying
Whenever this creature attacks, each player chooses a card name. Then each player reveals the top card of their library. If the card a player revealed has the name they chose, that player puts it into their hand. If it doesn't, that player puts it on the bottom of their library.

Sakashima the Impostor

You may have Sakashima the Impostor enter as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return Sakashima the Impostor to its owner's hand at the beginning of the next end step."

Soporific Springs

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {U}.

Sink into Stupor

Return target spell or nonland permanent an opponent controls to its owner's hand.

Sink into Stupor // Soporific Springs

Flooded Strand

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Witch-Blessed Meadow

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {W}.

Witch Enchanter

When this creature enters, destroy target artifact or enchantment an opponent controls.

Witch Enchanter // Witch-Blessed Meadow

Sea Gate, Reborn

Sea Gate Restoration

Draw cards equal to the number of cards in your hand plus one. You have no maximum hand size for the rest of the game.

Sea Gate Restoration // Sea Gate, Reborn

Master of Predicaments

Flying
Whenever this creature deals combat damage to a player, choose a card in your hand. That player guesses whether the card's mana value is greater than 4. If the player guessed wrong, you may cast the card without paying its mana cost.

Fell Mire

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}.

Fell the Profane

Fell the Profane // Fell Mire

Irenicus's Vile Duplication

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

Y'shtola Rhul

At the beginning of your end step, exile target creature you control, then return it to the battlefield under its owner's control. Then if it's the first end step of the turn, there is an additional end step after this step.

Watery Grave

({T}: Add {U} or {B}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Nanogene Conversion

Choose target creature you control. Each other creature becomes a copy of that creature until end of turn, except it isn't legendary.

Split Decision

Will of the council — Choose target instant or sorcery spell. Starting with you, each player votes for denial or duplication. If denial gets more votes, counter the spell. If duplication gets more votes or the vote is tied, copy the spell. You may choose new targets for the copy.

City of Brass

Whenever this land becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Become Anonymous

Exile target nontoken creature you own and the top two cards of your library in a face-down pile, shuffle that pile, then cloak those cards. They enter tapped. (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.)

The Toymaker's Trap

At the beginning of your upkeep, secretly choose a number between 1 and 5 that hasn't been chosen. If you do, an opponent guesses which number you chose, then you reveal the number you chose. If they guessed wrong, they lose life equal to the number they guessed and you draw a card. If they guessed right, sacrifice this enchantment.

Yennett, Cryptic Sovereign

Flying, vigilance, menace
Whenever Yennett attacks, reveal the top card of your library. You may cast it without paying its mana cost if its mana value is odd. If you don't cast it, draw a card.

Brilliant Ultimatum

Exile the top five cards of your library. An opponent separates those cards into two piles. You may play lands and cast spells from one of those piles. If you cast a spell this way, you cast it without paying its mana cost.

Sphinx Ambassador

Flying
Whenever this creature deals combat damage to a player, search that player's library for a card, then that player chooses a card name. If you searched for a creature card that doesn't have that name, you may put it onto the battlefield under your control. Then that player shuffles.

Sakashima of a Thousand Faces

You may have Sakashima enter as a copy of another creature you control, except it has Sakashima's other abilities.
The "legend rule" doesn't apply to permanents you control.
Partner (You can have two commanders if both have partner.)

Plains

Island

Shattered Sanctum

This land enters tapped unless you control two or more other lands.
{T}: Add {W} or {B}.

Command Tower

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

Path of Ancestry

This land enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Auton Soldier

You may have this creature enter as a copy of any creature on the battlefield, except it isn't legendary, is an artifact in addition to its other types, and has myriad. (Whenever it 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.)

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

The Celestial Toymaker

Whenever The Celestial Toymaker attacks, look at the top three cards of your library. Exile any number of them in a face-down pile and the rest in a face-up pile. Defending player chooses one of those piles. Put that pile into your hand.
At the beginning of each end step, each opponent loses 2 life for each spell or ability that caused one or more players to guess or to group cards or permanents into a pile this turn.

Bleachbone Verge

{T}: Add {B}.
{T}: Add {W}. Activate only if you control a Plains or a Swamp.

Sol Ring

Vault of Champions

This land enters tapped unless you have two or more opponents.
{T}: Add {W} or {B}.

Shizo, Death's Storehouse

{T}: Add {B}.
{B}, {T}: Target legendary creature gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)

Magister Sphinx

Flying
When this creature enters, target player's life total becomes 10.

Hallowed Fountain

({T}: Add {W} or {U}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Adric, Mathematical Genius

{2}{U}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
Ultimate Sacrifice — {1}{U}, Sacrifice Adric: Counter target activated or triggered ability.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard this card: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Quantum Misalignment

Create a token that's a copy of target creature you control, except it isn't legendary.
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.)

Sphinx of Uthuun

Flying
When this creature enters, reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

The Black Gate

As The Black Gate enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}.
{1}{B}, {T}: Choose a player with the most life or tied for most life. Target creature can't be blocked by creatures that player controls this turn.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Gollum, Scheming Guide

Whenever Gollum attacks, look at the top two cards of your library, put them back in any order, then choose land or nonland. An opponent guesses whether the top card of your library is the chosen kind. Reveal that card. If they guessed right, remove Gollum from combat. Otherwise, you draw a card and Gollum can't be blocked this turn.

Marsh Flats

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Orzhov Signet

Mana Confluence

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

Talon Gates of Madara

When this land enters, up to one target creature phases out.
{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{4}: Put this card from your hand onto the battlefield.

Deadly Rollick

If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Sheltered by Ghosts

Enchant creature you control
When this Aura enters, exile target nonland permanent an opponent controls until this Aura leaves the battlefield.
Enchanted creature gets +1/+0 and has lifelink and ward {2}.

Roaming Throne

Ward {2}
As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Sea of Clouds

This land enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Wound Reflection

At the beginning of each end step, each opponent loses life equal to the life they lost this turn. (Damage causes loss of life.)

Fact or Fiction

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Silver Shroud Costume

Flash
When this Equipment enters, attach it to target creature you control. That creature gains shroud until end of turn. (It can't be the target of spells or abilities.)
Equipped creature can't be blocked.
Equip {3}

Death or Glory

Separate all creature cards in your graveyard into two piles. Exile the pile of an opponent's choice and return the other to the battlefield.

Godless Shrine

({T}: Add {W} or {B}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Everybody Lives!

All creatures gain hexproof and indestructible until end of turn. Players gain hexproof until end of turn. Players can't lose life this turn and players can't lose the game or win the game this turn.

Atris, Oracle of Half-Truths

Menace
When Atris enters, target opponent looks at the top three cards of your library and separates them into a face-down pile and a face-up pile. Put one pile into your hand and the other into your graveyard.

Fellwar Stone

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

Arcane Signet

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Gogo, Master of Mimicry

{X}{X}, {T}: Copy target activated or triggered ability you control X times. You may choose new targets for the copies. This ability can't be copied and X can't be 0. (Mana abilities can't be targeted.)

Jace, Architect of Thought

+1: Until your next turn, whenever a creature an opponent controls attacks, it gets -1/-0 until end of turn.
−2: Reveal the top three cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other on the bottom of your library in any order.
−8: For each player, search that player's library for a nonland card and exile it, then that player shuffles. You may cast those cards without paying their mana costs.

Bloodletter of Aclazotz

Flying
If an opponent would lose life during your turn, they lose twice that much life instead. (Damage causes loss of life.)

Artful Dodge

Target creature can't be blocked this turn.
Flashback {U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Space Beleren

Space sculptor (Space Beleren divides the battlefield into alpha, beta, and gamma sectors. If a creature isn't assigned to a sector, its controller assigns it to one. Opponents assign first.)
+1: Creatures in each sector can be blocked this turn only by creatures in the same sector.
−1: Put a +1/+1 counter on each creature in the sector of your choice.
−5: Destroy all creatures in the sector of your choice.

Glasspool Shore

Glasspool Mimic

You may have this creature enter as a copy of a creature you control, except it's a Shapeshifter Rogue in addition to its other types.

Glasspool Mimic // Glasspool Shore

Fabled Passage

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Azorius Signet

Exotic Orchard

Starfall Invocation

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Destroy all creatures. If the gift was promised, return a creature card put into your graveyard this way to the battlefield under your control.

Truth or Tale

Reveal the top five cards of your library and separate them into two piles. An opponent chooses one of those piles. Put a card from the chosen pile into your hand, then put all other cards revealed this way on the bottom of your library in any order.

Raffine's Tower

({T}: Add {W}, {U}, or {B}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Unesh, Criosphinx Sovereign

Flying
Sphinx spells you cast cost {2} less to cast.
Whenever Unesh or another Sphinx you control enters, reveal the top four cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Epiphany at the Drownyard

Reveal the top X plus one cards of your library and separate them into two piles. An opponent chooses one of those piles. Put that pile into your hand and the other into your graveyard.

Strionic Resonator

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

MacCready, Lamplight Mayor

Whenever a creature you control with power 2 or less attacks, it gains skulk until end of turn. (It can't be blocked by creatures with greater power.)
Whenever a creature with power 4 or greater attacks you, its controller loses 2 life and you gain 2 life.

Curator of Destinies

This spell can't be countered.
Flying
When this creature enters, look at the top five cards of your library and separate them into a face-down pile and a face-up pile. An opponent chooses one of those piles. Put that pile into your hand and the other into your graveyard.

Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on this artifact.
At the beginning of each upkeep, put an hour counter on this artifact.
When the twelfth hour counter is put on this artifact, shuffle your hand and graveyard into your library, then draw seven cards. Exile this artifact.

Morphic Pool

This land enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Hostile Negotiations

Exile the top three cards of your library in a face-down pile, then exile the top three cards of your library in another face-down pile. Look at the cards in each pile, then turn a pile of your choice face up. An opponent chooses one of those piles. Put that pile into your hand and the other into your graveyard. You lose 3 life.

Do or Die

Separate all creatures target player controls into two piles. Destroy all creatures in the pile of that player's choice. They can't be regenerated.

Dimir Signet

Parallel Thoughts

When this enchantment enters, search your library for seven cards, exile them in a face-down pile, and shuffle that pile. Then shuffle your library.
If you would draw a card, you may instead put the top card of the pile you exiled into your hand.

Polluted Delta

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Arcane Sanctum

This land enters tapped.
{T}: Add {W}, {U}, or {B}.

Shipwreck Marsh

This land enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Deserted Beach

This land enters tapped unless you control two or more other lands.
{T}: Add {W} or {U}.

Sauron's Ransom

Choose an opponent. They look at the top four cards of your library and separate them into a face-down pile and a face-up pile. Put one pile into your hand and the other into your graveyard. The Ring tempts you.

Loran of the Third Path

Vigilance
When Loran enters, destroy up to one target artifact or enchantment.
{T}: You and target opponent each draw a card.

Malakir Mire

Malakir Rebirth

Choose target creature. You lose 2 life. Until end of turn, that creature gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Malakir Rebirth // Malakir Mire

Delney, Streetwise Lookout

Creatures you control with power 2 or less can't be blocked by creatures with power 3 or greater.
If an ability of a creature you control with power 2 or less triggers, that ability triggers an additional time.

Swamp

Fight or Flight

At the beginning of combat on each opponent's turn, separate all creatures that player controls into two piles. Only creatures in the pile of their choice can attack this turn.

The Seventh Doctor

Whenever The Seventh Doctor attacks, choose a card in your hand. Defending player guesses whether that card's mana value is greater than the number of artifacts you control. If they guessed wrong, you may cast it without paying its mana cost. If you don't cast a spell this way, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Minas Morgul, Dark Fortress

Minas Morgul enters tapped.
{T}: Add {B}.
{3}{B}, {T}: Put a shadow counter on target creature. For as long as that creature has a shadow counter on it, it's a Wraith in addition to its other types. (A creature with shadow can block or be blocked by only creatures with shadow.)

Make an Example

Each opponent separates the creatures they control into two piles. For each opponent, you choose one of their piles. Each opponent sacrifices the creatures in their chosen pile. (Piles can be empty.)

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.)