msem-instigator

Knight creatures you control have vigilance.
{2}{G}{W}: Put a +1/+1 counter on each creature you control.

At the beginning of your upkeep, Reality Collapse deals 1 damage to each opponent.
{2}{R}: Until end of turn, whenever an opponent is dealt noncombat damage, Reality Collapse deals that much damage to target creature that player controls.

Flying

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.”

{T}: Add {C}.
{T}, Reappropriate: Add one mana of any color. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)

{T}: Add {C}.
{1}, {T}: Add one mana of any color. This ability costs {1} less to activate if there are three or more colors among cards in your graveyard.

(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.

When Realmwalker Domovoi enters, exile another target permanent you control. Return it to the battlefield under your control at the beginning of the next end step.

Reach
Whenever you cast a spell with mana value 5 or greater, Reaper Squad deals 3 damage to target player or planeswalker.

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

Enchant creature
Enchanted creature has deathtouch and “When this creature dies, create a 2/2 black Demon creature token.”
{1}{B}, Exile Reaping Mask from your graveyard: Create a 2/2 black Demon creature token.

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.

(Activate each submodule once as a sorcery. When this enters, activate one submodule for free.)
{2}{B}: Reduce
You may sacrifice a nonland permanent. If you do, each opponent sacrifices a permanent that shares a type with it.
{2}{G}: Reuse
Return target permanent card from your graveyard to your hand.
{1}{B}{G}: Recycle
Rebirth Module gains “Once each turn, when you sacrifice a permanent, you may conjure a card named Data-Point into your hand.” (It's a sorcery that costs {2} with “Draw a card.”)

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

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.

{T}, Sacrifice a land: Untap up to three target lands.

Haste
Whenever Reckless Dunerider attacks, if it's enchanted or equipped, you may draw a card. If you do, discard a card.

Trample
When Reckless Exemplar attacks, if its power is greater than its base power, target creature an opponent controls can't block this turn.

Rhapsody {4}{R}{R} (Pay {4}{R}{R} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
When Reckless Guardian dies, create X 1/1 colorless Servo artifact creature tokens, where X is Reckless Guardian's power.

{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.

Haste
Whenever Reckless Pyremage becomes tapped, it deals 1 damage to each creature and each player.

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} ({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.