msem-instigator

Choose one or both —
• Each player shuffles their hand and graveyard into their library, then draws seven cards.
• Each player may put a permanent card from their hand onto the battlefield.
Exile Reality Rewoven.

Flying, ward {2}
Whenever Realm Crossers deals combat damage to a player, create a blue enchantment token named Tambo with “At the beginning of your upkeep, draw a card if you control a Scout.”

Whenever a nontoken creature with mana value 3 or less you control enters, exile it. If you do, create a token that's a copy of it, except it's a Construct creature instead of its other types.

Rediscover an artifact card, then do the same for creature, enchantment, instant, land, planeswalker, and sorcery. (Each time, look at the top card of your library. You may reveal it and put it into your hand if it's of that type. Otherwise, put it back or into your graveyard.)

Counter target spell unless its controller pays {1}. If they do, draw a card.

Return target instant or sorcery card from your graveyard to your hand.
Draw a card.

Whenever you cast a noncreature spell, you may put a progress counter on Reckless Research.
[progress 2+] At the beginning of your end step, mill two cards.
[progress 7+] At the beginning of your upkeep, choose target instant or sorcery card in your graveyard. You may cast it from your graveyard this turn.
At the beginning of your upkeep, choose target instant or sorcery card in your graveyard. You may cast it from your graveyard this turn.

Flash
{U}, Return another creature you control to its owner's hand: Reclusive Archmage can't be blocked this turn and gains hexproof until end of turn. Activate only once each turn.

Hexproof
Paranoia {1}{U} (You may cast this spell for its paranoia cost when a permanent you control leaves the battlefield.)

When Recognification Process enters and at the beginning of your upkeep, create a token that's a copy of target artifact you control, then sacrifice an artifact.

Target spell's controller manifests it. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Choose one —
• Counter target spell unless its controller pays {2}.
• Draw a card.

Flash
Prowess
When Reconstructed Adept enters, target instant or sorcery card in your graveyard gains agonize until end of turn. (You may cast it by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile that card.)

Deception {U} ({U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever a Pirate or Rogue you control deals combat damage to a player, rediscover a Pirate or Rogue card. (Look at the top card of your library. You may reveal it and put it into your hand if it's a Pirate or Rogue. Otherwise, put it back or into your graveyard.)

When Recruits of the Demeter enters, draw a card if you control another Pirate.

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.)

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Counter target spell unless its controller pays its mana cost. (For example, if a spell costs {1}{U}{U}, its controller must pay {1}{U}{U}.)

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.”)

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)
Counter target creature spell. If this spell was kicked, create a 1/1 colorless Thopter artifact creature token with flying.

Converge — Exile up to X nonland permanents you control, where X is the number of colors of mana spent to cast Reenter Orbit, then return them to the battlefield under your control.

Draw two cards, then discard a card.

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.)

Flying
{2}{U}: Switch target creature's power and toughness until end of turn.

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Shimmer (Whenever this creature attacks, create a tapped and attacking token that's a copy of it. Exile the token at the beginning of the next end step.)