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.

Sphinx of Foresight

You may reveal this card from your opening hand. If you do, scry 3 at the beginning of your first upkeep.
Flying
At the beginning of your upkeep, scry 1.

Perpetual Timepiece

{T}: Mill two cards.
{2}, Exile this artifact: Shuffle any number of target cards from your graveyard into your library.

Warden of Evos Isle

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

Vexing Sphinx

Flying
Cumulative upkeep—Discard a card. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
When this creature dies, draw a card for each age counter on it.

Unwinding Clock

Untap all artifacts you control during each other player's untap step.

Treasure Cove

(Transforms from Treasure Map.)
{T}: Add {C}.
{T}, Sacrifice a Treasure: Draw a card.

Treasure Map

{1}, {T}: Scry 1. Put a landmark counter on this artifact. Then if there are three or more landmark counters on it, remove those counters, transform this artifact, and create three Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Treasure Map // Treasure Cove

Herald's Horn

As this artifact enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Fetid Pools

({T}: Add {U} or {B}.)
This land enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Call to the Kindred

Enchant creature
At the beginning of your upkeep, you may look at the top five cards of your library. If you do, you may put a creature card that shares a creature type with enchanted creature from among them onto the battlefield, then you put the rest of those cards on the bottom of your library in any order.

Sunken Hollow

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

Medomai the Ageless

Flying
Whenever Medomai deals combat damage to a player, take an extra turn after this one.
Medomai can't attack during extra turns.

Watery Grave

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

Sanctum of the Sun

(Transforms from Azor's Gateway.)
{T}: Add X mana of any one color, where X is your life total.

Azor's Gateway

{1}, {T}: Draw a card, then exile a card from your hand. If cards with five or more different mana values are exiled with Azor's Gateway, you gain 5 life, untap Azor's Gateway, and transform it.

Azor's Gateway // Sanctum of the Sun

Godless Shrine

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

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.

Tezzeret the Seeker

+1: Untap up to two target artifacts.
−X: Search your library for an artifact card with mana value X or less, put it onto the battlefield, then shuffle.
−5: Artifacts you control become artifact creatures with base power and toughness 5/5 until end of turn.

Planar Bridge

{8}, {T}: Search your library for a permanent card, put it onto the battlefield, then shuffle.

Sol Ring

Commander's Sphere

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

Dromar's Cavern

When this land enters, sacrifice it unless you return a non-Lair land you control to its owner's hand.
{T}: Add {W}, {U}, or {B}.

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.

Sandstone Oracle

Flying
When this creature enters, choose an opponent. If that player has more cards in hand than you, draw cards equal to the difference.

Bojuka Bog

This land enters tapped.
When this land enters, exile target player's graveyard.
{T}: Add {B}.

Fortune's Favor

Target opponent looks at the top four 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.

Wayfarer's Bauble

{2}, {T}, Sacrifice this artifact: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Isperia, Supreme Judge

Flying
Whenever a creature attacks you or a planeswalker you control, you may draw a card.

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.

Karn, the Great Creator

Activated abilities of artifacts your opponents control can't be activated.
+1: Until your next turn, up to one target noncreature artifact becomes an artifact creature with power and toughness each equal to its mana value.
−2: You may reveal an artifact card you own from outside the game or choose a face-up artifact card you own in exile. Put that card into your hand.

Dimir Signet

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.

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.

The Immortal Sun

Players can't activate planeswalkers' loyalty abilities.
At the beginning of your draw step, draw an additional card.
Spells you cast cost {1} less to cast.
Creatures you control get +1/+1.

Patriarch's Bidding

Each player chooses a creature type. Each player returns all creature cards of a type chosen this way from their graveyard to the battlefield.

Sapphire Medallion

Blue spells you cast cost {1} less to cast.

Metallic Mimic

As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
Each other creature you control of the chosen type enters with an additional +1/+1 counter on it.

Magister Sphinx

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

Glacial Fortress

This land enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

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.

Walking Ballista

This creature enters with X +1/+1 counters on it.
{4}: Put a +1/+1 counter on this creature.
Remove a +1/+1 counter from this creature: It deals 1 damage to any target.

Sphinx Summoner

Flying
When this creature enters, you may search your library for an artifact creature card, reveal it, put it into your hand. then shuffle.

Utter End

Azor, the Lawbringer

Flying
When Azor enters, each opponent can't cast instant or sorcery spells during that player's next turn.
Whenever Azor attacks, you may pay {X}{W}{U}{U}. If you do, you gain X life and draw X cards.

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.

Isolated Chapel

This land enters tapped unless you control a Plains or a Swamp.
{T}: Add {W} or {B}.

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. This land deals 1 damage to you.

Ancient Den

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice this artifact: Draw two cards.

Swamp

Consecrated Sphinx

Flying
Whenever an opponent draws a card, you may draw two cards.

Windreader Sphinx

Flying
Whenever a creature with flying attacks, you may draw a card.

Sphinx of Magosi

Flying
{2}{U}: Draw a card, then put a +1/+1 counter on this creature.

Azorius Signet

Seat of the Synod

Sphinx's Revelation

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Urza's Incubator

As this artifact enters, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.

Unclaimed Territory

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

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}

Arcane Sanctum

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

Coalition Relic

{T}: Add one mana of any color.
{T}: Put a charge counter on this artifact.
At the beginning of your first main phase, remove all charge counters from this artifact. Add one mana of any color for each charge counter removed this way.

Sharuum the Hegemon

Flying
When Sharuum enters, you may return target artifact card from your graveyard to the battlefield.

Command Tower

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

One with the Machine

Draw cards equal to the highest mana value among artifacts you control.

Etherium Sculptor

Artifact spells you cast cost {1} less to cast.

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Thirst for Knowledge

Draw three cards. Then discard two cards unless you discard an artifact card.

Sharding Sphinx

Flying
Whenever an artifact creature you control deals combat damage to a player, you may create a 1/1 blue Thopter artifact creature token with flying.

Ugin, the Ineffable

Colorless spells you cast cost {2} less to cast.
+1: Exile the top card of your library face down and look at it. Create a 2/2 colorless Spirit creature token. When that token leaves the battlefield, put the exiled card into your hand.
−3: Destroy target permanent that's one or more colors.

Cavern of Souls

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Vault of Whispers

Noxious Gearhulk

Menace
When this creature enters, you may destroy another target creature. If a creature is destroyed this way, you gain life equal to its toughness.

Tezzeret, Master of the Bridge

Creature and planeswalker spells you cast have affinity for artifacts. (They cost {1} less to cast for each artifact you control.)
+2: Tezzeret deals X damage to each opponent, where X is the number of artifacts you control. You gain X life.
−3: Return target artifact card from your graveyard to your hand.
−8: Exile the top ten cards of your library. Put all artifact cards from among them onto the battlefield.

Azorius Chancery

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Thran Dynamo

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Prairie Stream

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

Swords to Plowshares

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

Jhoira's Familiar

Flying
Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. This land deals 1 damage to you.

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.)

Vedalken Orrery

You may cast spells as though they had flash.

Irrigated Farmland

({T}: Add {W} or {U}.)
This land enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Orzhov Signet

Hallowed Fountain

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

Inventors' Fair

At the beginning of your upkeep, if you control three or more artifacts, you gain 1 life.
{T}: Add {C}.
{4}, {T}, Sacrifice Inventors' Fair: Search your library for an artifact card, reveal it, put it into your hand, then shuffle. Activate only if you control three or more artifacts.

Drowned Catacomb

This land enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Sphinx of the Steel Wind

Flying, first strike, vigilance, lifelink, protection from red and from green

Sphinx of Lost Truths

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
Flying
When this creature enters, draw three cards. Then if it wasn't kicked, discard three cards.

Island

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Plains

Phyrexian Metamorph

({U/P} can be paid with either {U} or 2 life.)
You may have this creature enter as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Return target artifact card from your graveyard to your hand.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Mana Vault

This artifact doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {4}. If you do, untap this artifact.
At the beginning of your draw step, if this artifact is tapped, it deals 1 damage to you.
{T}: Add {C}{C}{C}.