Land Equilibrium

If an opponent who controls at least as many lands as you do would put a land onto the battlefield, that player instead puts that land onto the battlefield then sacrifices a land.

Arcane Signet

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

Thassa's Oracle

When Thassa's Oracle enters the battlefield, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Stasis

Players skip their untap steps.
At the beginning of your upkeep, sacrifice Stasis unless you pay {U}.

Counterspell

Sol Ring

Pendrell Mists

All creatures have "At the beginning of your upkeep, sacrifice this creature unless you pay {1}."

Dramatic Reversal

Untap all nonland permanents you control.

Telepathy

Your opponents play with their hands revealed.

Equilibrium

Whenever you cast a creature spell, you may pay {1}. If you do, return target creature to its owner's hand.

Embargo

Nonland permanents don't untap during their controllers' untap steps.
At the beginning of your upkeep, you lose 2 life.

Zur's Weirding

Players play with their hands revealed.
If a player would draw a card, they reveal it instead. Then any other player may pay 2 life. If a player does, put that card into its owner's graveyard. Otherwise, that player draws a card.

Back to Basics

Nonbasic lands don't untap during their controllers' untap steps.

Daze

You may return an Island you control to its owner's hand rather than pay this spell's mana cost.
Counter target spell unless its controller pays {1}.

Overburden

Whenever a player puts a nontoken creature onto the battlefield, that player returns a land they control to its owner's hand.

Rising Waters

Lands don't untap during their controllers' untap steps.
At the beginning of each player's upkeep, that player untaps a land they control.

Mana Vortex

When you cast this spell, counter it unless you sacrifice a land.
At the beginning of each player's upkeep, that player sacrifices a land.
When there are no lands on the battlefield, sacrifice Mana Vortex.

Sunder

Leadership Vacuum

Target player returns each commander they control from the battlefield to the command zone.
Draw a card.

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.

Sigil of Sleep

Enchant creature
Whenever enchanted creature deals damage to a player, return target creature that player controls to its owner's hand.

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Mana Short

Tap all lands target player controls and that player loses all unspent mana.

Shimmer

As Shimmer enters the battlefield, choose a land type.
Each land of the chosen type has phasing. (It phases in or out before its controller untaps during each of their untap steps. While it's phased out, it's treated as though it doesn't exist.)

Negate

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Isochron Scepter

Imprint — When Isochron Scepter enters the battlefield, you may exile an instant card with mana value 2 or less from your hand.
{2}, {T}: You may copy the exiled card. If you do, you may cast the copy without paying its mana cost.