msem-instigator

Up to X target creatures gain winnow until end of turn. (Damage dealt to a creature with winnow also causes its controller to lose that much life.)
Rain of Ruin deals 2 damage to each creature.

({T}: Add {G} or {U}.)
Rainforest Spring enters tapped.

Haste
When Rainy Night Lovers enters, look at the top four cards of your library. You may cast a red instant or sorcery spell with mana value 1 from among them without paying its mana cost. Then put the rest on the bottom of your library in any order.

Create two 1/1 white Soldier creature tokens.

Trample
Art of war — At the beginning of your end step, if Raiun Bay Admiral dealt damage to an opponent this turn, put a +1/+1 counter on each other creature you control.

Haste
Whenever a player casts a spell, Rakkiri Dissident deals 1 damage to that player.

Indestructible
Battalion — Whenever Rallios, Heir to the Evil One and at least two other creatures attack, creatures you control get +1/+0 and gain double strike until end of turn.

Ralora, Unforgiving Depths enters tapped.
Whenever a source deals damage to you, put a creation counter on Ralora.
{T}, Remove ten creation counters from Ralora and sacrifice it: It deals 10 damage to target player or planeswalker.

At the beginning of your upkeep, mill two cards.

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

({T}: Add {R} or {G}.)
Whenever Rampant Summit becomes tapped, you lose 1 life unless you control two or more basic lands.

When Ramzi, Traveling Merchant enters, adjudicate land. (Create a white enchantment Aura token with enchant land and “Sacrifice this token: Untap enchanted land.” attached to target land.)
Whenever an Aura becomes attached to a land you control, create a 1/1 green Antelope creature token.

Target creature you control gets +1/+1 and gains hexproof until end of turn.

Sacrifice a creature: Rapacious Demon gets +1/+1 and gains flying until end of turn. Activate only as a sorcery.

First strike
When Rapacious Rattler enters, choose one or two targets you don't control. It deals 2 damage to the first and 1 damage to the second.

Flying
When Rapacious Regent enters, you may sacrifice another creature or artifact. If you do, Rapacious Regent deals 3 damage to any target.

Haste
Whenever Rapid Rodent attacks, it gets +1/+0 until end of turn for each other creature you control with flash and/or haste.

Whenever Ravaging Tyrant enters or attacks, each opponent loses 3 life, discards a card, and sacrifices a creature or planeswalker.

When Ravenous Chupacabra enters, destroy target creature an opponent controls.

Ravenous Hydra enters with X +1/+1 counters on it.
Whenever Ravenous Hydra deals combat damage, proliferate. (You choose any number of permanents and/or players with counters on them, then give each another kind of a counter already there.)

You may return a land you control to its owner's hand rather than pay this spell's mana cost.
Rawthlin Market Line enters tapped.
{T}: Add {G}.

{T}: Add {C}.
{2}, {T}: Target creature gains haste until end of turn.

Scry 2, then draw a card.
If you control a legendary permanent, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Create two 1/1 colorless Servo artifact creature tokens.
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.)

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.”