msem-instigator

As an additional cost to cast Reality Reversal, return X nonland permanents you control to their owners' hands.
Return X plus one target nonland permanents to their owners' hands.

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.”

(Activate each ability only once as a sorcery. You gain the realm's favor after activating them all.)
{1}: Search your library for a legendary creature card, reveal it, put it into your hand, then shuffle.
{2}: Invigorate 5. (Choose a creature with the least power among creatures you control and put five +1/+1 counters on it.)
{3}: Draw cards equal to the greatest power among creatures you control.
Other permanents you control have hexproof and indestructible.

Reveal the top X cards of your library, where X is the number of lands you control. Put any number of permanent cards revealed this way onto the battlefield and the rest on the bottom of your library in a random order.

Whenever a Plains you control enters, you may put a creature card with mana value 2 or less from your hand onto the battlefield.

You may have Reaping Willow assign its combat damage as though it weren't blocked.
{2}{G}: Reaping Willow gains indestructible until end of turn.

As Reborn Altar enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {R}, {W}, or {B}.

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.

Exile target instant or sorcery spell you control. Until end of turn, you may cast that card from exile without paying its mana cost. When you do, copy it. You may choose new targets for the copy.

Choose two or four —
• Each opponent sacrifices an artifact.
• Create a 1/1 red Warrior creature token.
• Creatures you control get +1/+0 and gain trample and haste until end of turn.
• Conjure a card named Fatigue and put it on top of your library. (It's a colorless sorcery that costs {2} with “Draw a card.”)

Exile the top three cards of your library. Until the end of your next turn, you may cast nonland cards exiled this way.
{3}{U}{R}: Return Reckless Experiment from your graveyard to the
battlefield tapped and transformed.

Starting with you, each player either passes or reveals the top card of their library. Each player that revealed a card this way pays life equal to its mana value. If a player can't, that player passes. Then each player who hasn't passed yet puts that card into their hand. Repeat this process until each player has passed.

{T}: Target creature gains haste until end of turn.
{1}{R}, {T}, Sacrifice a Human: Create a token that's a copy of the sacrificed creature, except it's a 3/2 colorless Horror. It gains haste until end of turn. Activate only as a sorcery.

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.

Lionize {1}{B} ({1}{B}, Exile this card from your hand: Put a +1/+1 counter on target creature and it gains the following abilities until end of turn. You may cast this card on a later turn from exile.)
Flying, lifelink
Whenever this creature deals combat damage to a player, remove all counters from target permanent they control or protect.

Trial 6 (As you cast this spell, an opponent of your choice may pay 6 life. If they don't, they fail the trial.)
Flying
When Reckoner of Man enters, if the trial was failed, it deals 3 damage to each creature you don't control.

Whenever Reclamation Grovesculptor enters or attacks, put a growth counter on target noncreature permanent. It becomes a colorless Forest land and loses all other card types and land types.

Whenever a creature you control deals combat damage to an opponent or planeswalker, put a technology counter on Reclamation Project.
Remove X technology counters from Reclamation Project: You may cast target artifact or creature card with mana value X from your graveyard this turn. That creature enters as an artifact in addition to its other types. X can't be 0.

When Reclamation Sage enters, you may destroy target artifact or enchantment.

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.

{2}{B}{B}, Exile Reclusive Augur from your graveyard: Return another target creature card from your graveyard to the battlefield. Activate only during your turn.

Reclusive Copse enters tapped.
{T}: Add {B} or {G}.
{1}{B}{G}: Until end of turn, Reclusive Copse becomes an Insect creature with deathtouch in addition to its other types.
Scavenge {B}{G}

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.