Mox Diamond

If this artifact would enter, you may discard a land card instead. If you do, put this artifact onto the battlefield. If you don't, put it into its owner's graveyard.
{T}: Add one mana of any color.

Skycloud Expanse

Claws of Gix

{1}, Sacrifice a permanent: You gain 1 life.

Oboro, Palace in the Clouds

{T}: Add {U}.
{1}: Return Oboro to its owner's hand.

Balance

Each player chooses a number of lands they control equal to the number of lands controlled by the player who controls the fewest, then sacrifices the rest. Players discard cards and sacrifice creatures the same way.

Rule of Law

Each player can't cast more than one spell each turn.

Muddle the Mixture

Counter target instant or sorcery spell.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Serum Visions

Adarkar Wastes

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

Copper-Leaf Angel

Flying
{T}, Sacrifice X lands: Put X +1/+1 counters on this creature.

Erayo's Essence

Whenever an opponent casts their first spell each turn, counter that spell.

Erayo, Soratami Ascendant

Flying
Whenever the fourth spell of a turn is cast, flip Erayo.

Erayo, Soratami Ascendant // Erayo's Essence

Court Hussar

Vigilance
When this creature enters, look at the top three cards of your library, then put one of them into your hand and the rest on the bottom of your library in any order.
When this creature enters, sacrifice it unless {W} was spent to cast it.

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Jeweled Amulet

{1}, {T}: Put a charge counter on this artifact. Note the type of mana spent to pay this activation cost. Activate only if there are no charge counters on this artifact.
{T}, Remove a charge counter from this artifact: Add one mana of this artifact's last noted type.

Azorius Chancery

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