msem-instigator

{2}{B}: Reclaimed Kalak gains indestructible until end of turn.
Revive {3}{W} ({3}{W}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

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.

Flash

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}

As an additional cost to cast this spell, pay {2} or sacrifice a creature.
Menace

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.

Flash
Creatures your opponents control have base power and toughness 1/1.
Fleeting {1}{W}{W} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

When Recollection Revelation enters, rouse 1. (Put a +1/+1 counter on a permanent you control. If it isn't a creature, tap it and it becomes a 0/0 creature in addition to its other types.)
{1}{W}, Sacrifice Recollection Revelation: Return another target artifact or enchantment card from your graveyard to your hand.

Menace
Crew 2 (Tap any number of creatures you control with total power 2 or greater: This Vehicle becomes an artifact creature until end of turn.)

When Recon Drone enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle. Then if you did, put a card from your hand on the bottom of your library.

Flash
{1}, {T}: Scry 1.

When Reconnaissance Expert enters, mill four cards.
When Reconnaissance Expert dies, return target noncreature permanent card from your graveyard to your hand.

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.)

Flying, lifelink
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever Recreator of Myths attacks, you may cast target instant or sorcery spell from your graveyard. If you do, exile that card instead of putting it into your graveyard as it resolves.

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.

Whenever Recurring Abomination deals combat damage to an opponent, you may put target creature card with mana value 3 or less from a graveyard onto the battlefield under your control.
{4}{B}{B}: Return Recurring Abomination from your graveyard to the battlefield tapped.

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.)

When Red Flower Assassin enters, destroy target creature.
Revive {5}{B} ({5}{B}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Trample, haste
When Red Pelt Hart deals combat damage to a player, return it to its owner's hand.
At the beginning of your end step, sacrifice Red Pelt Hart.