msem-instigator

When Recursion Runner enters, create a Function token with “If this spell isn't a copy, copy it. You may choose new targets for the copy.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Counter target spell.
Create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

Take an extra turn after this one. If this spell was cast from exile, take two extra turns after this one instead. Shuffle Reflected Moment into its owner's main library.
Prophecy {6}{U}{U} (Once each turn, you may exile a card with prophecy as you reveal it. When you do, you may cast it for its prophecy cost as long as it's exiled.)

Indestructible
When Reflected Worldwalker enters, each player puts their hand into their sideboard.

Destroy all creatures. If a Reflection would be destroyed this way, its owner shuffles it into their library instead.

Destroy all monocolored creatures.

Counter target spell.
{1}{U}, Exile Refute from your graveyard: Draw a card.

Each player sacrifices three lands. Regal Ignition deals 3 damage to each nonlegendary creature.

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
As long as you control three or more artifacts, Regal Seasnake has vigilance. (Attacking doesn't cause it to tap.)

This spell costs {1} less to cast for each artifact you control.
Search your library for an artifact creature card with mana value X or less, put it onto the battlefield, then shuffle.

Counter target spell.
Satrapycycling {2} ({2}, Discard this card: Search your library for a Satrapy card, reveal it, put it into your hand, then shuffle.)

Untap all basic lands you control.
Draw a card.

When Relentless Pathcutter enters, create a green Aura enchantment token named Enmity attached to target creature. The token has enchant creature and “Enchanted creature gets +2/+0 and has trample.”
When Relentless Pathcutter dies, return it to its owner's hand.

Search target opponent's library for an artifact card and put it onto the battlefield under your control, then that player shuffles. If you don't put a card onto the battlefield this way, create four Gold tokens. At the beginning of the next end step, sacrifice each artifact put onto the battlefield this way. (This includes the Gold.)

Flying
Whenever Reliya's Construct attacks, it gets +1/+1 until end of turn for each instant or sorcery card in your graveyard.
{U}{U}, {T}, Sacrifice Reliya's Construct: Return target instant or sorcery card from your graveyard to your hand.

Trample, haste
When Relonche Cavalry enters, other creatures you control get +1/+0 and gain trample and haste until end of turn.

Relonche Spy enters under the control of an opponent of your choice.
Relonche Spy can't block.
During each of Relonche Spy's owner's turns, they may cast a card from your graveyard by paying life equal to its mana value rather than paying its mana cost.

Choose a creature. Exile the rest.

Return target instant or sorcery card from your graveyard to your hand.
Leitmotif (If you cast this spell from your hand, exile it as it resolves. When you next cast a spell that shares a color with this card, you may cast this from exile without paying its mana cost.)

Trample
When Remnant of the Wild enters, if you cast it, untap all lands you control.

Exile target nonblack creature. Its controller exiles a card at random from their hand.

Protection from Illusions
All cards that aren't on the battlefield, spells, and other permanents are Illusion kindreds in addition to their other types.

When Renatured Vines enters, draw a card and create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
Renatured Vines power and toughness are each equal to the number of cards in your hand.

Destroy target creature or planeswalker. You gain 1 life and that permanent's controller loses 1 life.