Inspiration

Knight of the Mists

Flanking (Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn.)
When this creature enters, you may pay {U}. If you don't, destroy target Knight and it can't be regenerated.

Man-o'-War

When this creature enters, return target creature to its owner's hand.

Mystic Veil

You may cast this spell as though it had flash. If you cast it any time a sorcery couldn't have been cast, the controller of the permanent it becomes sacrifices it at the beginning of the next cleanup step.
Enchant creature
Enchanted creature has shroud. (It can't be the target of spells or abilities.)

Ovinomancer

Sheep

When this creature enters, sacrifice it unless you return three basic lands you control to their owner's hand.
{T}, Return this creature to its owner's hand: Destroy target creature. It can't be regenerated. That creature's controller creates a 0/1 green Sheep creature token.

Eye of Singularity

When this enchantment enters, destroy each permanent with the same name as another permanent, except for basic lands. They can't be regenerated.
Whenever a permanent other than a basic land enters, destroy all other permanents with that name. They can't be regenerated.

Prosperity

Rainbow Efreet

Flying
{U}{U}: This creature phases out. (While it's phased out, it's treated as though it doesn't exist. It phases in before you untap during your next untap step.)

Shimmering Efreet

Flying
Phasing (This phases in or out before you untap during each of your untap steps. While it's phased out, it's treated as though it doesn't exist.)
Whenever this creature phases in, target creature phases out. (It phases in before its controller untaps during their next untap step.)

Shrieking Drake

Flying
When this creature enters, return a creature you control to its owner's hand.

Teferi's Realm

At the beginning of each player's upkeep, that player chooses artifact, creature, land, or non-Aura enchantment. All nontoken permanents of that type phase out. (While they're phased out, they're treated as though they don't exist. Each one phases in before its controller untaps during their next untap step.)

Three Wishes

Exile the top three cards of your library face down. You may look at those cards for as long as they remain exiled. Until your next turn, you may play those cards. At the beginning of your next upkeep, put any of those cards you didn't play into your graveyard.

Time and Tide

Simultaneously, all phased-out creatures phase in and all creatures with phasing phase out.

Undo

Return two target creatures to their owners' hands.

Vanishing

Enchant creature
{U}{U}: Enchanted creature phases out. (While it's phased out, it's treated as though it doesn't exist. It phases in before its controller untaps during their next untap step.)

Vision Charm

Choose one —
• Target player mills four cards.
• Choose a land type and a basic land type. Each land of the first chosen type becomes the second chosen type until end of turn.
• Target artifact phases out. (While it's phased out, it's treated as though it doesn't exist. It phases in before its controller untaps during their next untap step.)

Visions