msem-instigator

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

Rakkiri Pathblazer gets +2/-1 as long as it's embattled. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Trample
When Rallios's Champion enters, look at the top six cards of your library. You may put a Warrior card with lesser mana value from among them onto the battlefield. Put the rest on the bottom of your library in a random order.
Other Warriors you control get +1/+1.

Create two 1/1 red Soldier creature tokens with haste.

As long as it's your turn, Rallying Rector has first strike.
Whenever Rallying Rector attacks, you may discard a card. If you do, search your library for a card named Rallying Rector, reveal it, put it into your hand, then shuffle.

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.

Whenever you cast a spell that doesn't share a color with Raloran Adept, you may switch target creature's power and toughness until end of turn.

Whenever Ram Wrangler attacks, until end of turn, gain control of target creature defending player controls with power less than or equal to the number of creatures in Ram Wrangler's pack. Tap it. It's attacking defending player. (Two or more creatures you control with equal power are in a pack.)

Reach (This creature can block creatures with flying.)
Whenever a land you control enters, Rammanethi Sandshaper deals 1 damage to target creature with flying.

Haste
Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)

Enchant creature you control
When Rapacious Instinct enters, enchanted creature deals damage equal to its power to target creature you don't control.
Enchanted creature gets +1/+0.

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.

Menace
When Rattled Bones dies, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)

When Ravenous Abomination enters, choose one —
• Create two Treasure tokens.
• Put a +1/+1 counter on Ravenous Abomination.

First strike, trample
Whenever a creature dealt combat damage by Ravenous Forsaken this turn dies, put a +1/+1 counter on Ravenous Forsaken.
{2}{R}: Ravenous Forsaken gets +3/+0 until end of turn.

Double strike

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.

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

Reason Rots, Rage Remains deals X damage to any target.
Reconstruct {X}{R}{R} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

Gain control of target creature until end of turn. Untap that creature. It gains haste and defiance until end of turn. (Whenever that creature takes damage, if it survives and wasn't defiant, put a +1/+1 counter on it and it becomes defiant.)

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.

Tap up to three target lands. They don't untap during their controller's next untap step.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

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