Mana Geyser

Add {R} for each tapped land your opponents control.

Talisman of Conviction

{T}: Add {C}.
{T}: Add {R} or {W}. Talisman of Conviction deals 1 damage to you.

Manifold Insights

Reveal the top ten cards of your library. Starting with the next opponent in turn order, each opponent chooses a different nonland card from among them. Put the chosen cards into your hand and the rest on the bottom of your library in a random order.

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.
{T}: Add {C}{C}.

Volcanic Island

Exotic Orchard

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

Grim Monolith

Grim Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{4}: Untap Grim Monolith.

Nimbus Maze

{T}: Add {C}.
{T}: Add {W}. Activate only if you control an Island.
{T}: Add {U}. Activate only if you control a Plains.

Flooded Strand

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

Hallowed Fountain

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

Talisman of Progress

{T}: Add {C}.
{T}: Add {W} or {U}. Talisman of Progress deals 1 damage to you.

Plateau

Mystic Gate

{T}: Add {C}.
{W/U}, {T}: Add {W}{W}, {W}{U}, or {U}{U}.

Thran Dynamo

Azorius Signet

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Arid Mesa

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

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Mana Vault

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

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. Battlefield Forge deals 1 damage to you.

Glacial Fortress

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

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Elsha of the Infinite

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
You may look at the top card of your library any time.
You may cast noncreature spells from the top of your library. If you cast a spell this way, you may cast it as though it had flash.

Scalding Tarn

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

Arcane Signet

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

Izzet Signet

Sacred Foundry

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

Fellwar Stone

Pact of Negation

Counter target spell.
At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Mystic Remora

Cumulative upkeep {1} (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.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Steam Vents

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

Tundra

Sea of Clouds

Sea of Clouds enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Rhystic Study

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

Boros Signet

Lion's Eye Diamond

Discard your hand, Sacrifice Lion's Eye Diamond: Add three mana of any one color. Activate only as an instant.

Divergent Transformations

Undaunted (This spell costs {1} less to cast for each opponent.)
Exile two target creatures. For each of those creatures, its controller reveals cards from the top of their library until they reveal a creature card, puts that card onto the battlefield, then shuffles the rest into their library.

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. Adarkar Wastes deals 1 damage to you.

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Stomping Ground

({T}: Add {R} or {G}.)
As Stomping Ground enters, you may pay 2 life. If you don't, it enters tapped.

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Command Tower

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.")

Expropriate

Council's dilemma — Starting with you, each player votes for time or money. For each time vote, take an extra turn after this one. For each money vote, choose a permanent owned by the voter and gain control of it. Exile Expropriate.