msem-instigator

({T}: Add {B} or {R}.)
As Ruptured Flats enters, you may pay {1}. If you don't, Ruptured Flats enters tapped.

({T}: Add {U} or {B}.)
As Ruptured Grotto enters, you may pay {1}. If you don't, Ruptured Grotto enters tapped.

({T}: Add {G} or {U}.)
As Ruptured Grove enters, you may pay {1}. If you don't, Ruptured Grove enters tapped.

({T}: Add {G} or {W}.)
As Ruptured Meadow enters, you may pay {1}. If you don't, Ruptured Meadow enters tapped.

({T}: Add {B} or {G}.)
As Ruptured Morass enters, you may pay {1}. If you don't, Ruptured Morass enters tapped.

({T}: Add {W} or {U}.)
As Ruptured Square enters, you may pay {1}. If you don't, Ruptured Square enters tapped.

({T}: Add {R} or {G}.)
As Ruptured Trail enters, you may pay {1}. If you don't, Ruptured Trail enters tapped.

Rushing Waters enters tapped.
{T}: Add {U} or {R}.
When Rushing Waters enters, you may put a loyalty counter on a planeswalker you control.

Flying
When Rushwater Hunter enters, you may return target creature to its owner's hand.

Improve {1}{U} ({1}{U}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
At the beginning of your end step, if one or more embattled creatures you controlled dealt damage to a player, you may draw a card. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

When Russet Denmother enters, choose one —
• Destroy target enchantment.
• Create a 2/1 red and white Fox creature token.

Rustshell Crustacean gets +1/+1 for each artifact you control.
Whenever Rustshell Crustacean attacks, choose one —
• Search your library for an Equipment card, reveal it, and put it into your hand, then shuffle.
• Create a Treasure token.

Whenever Rustshell Mantis is dealt damage, put that many +1/+1 counters on it. (It must survive the damage to get the counters.)

Deathtouch
Whenever Ruststep Centipede deals combat damage to a player, you may destroy target artifact or enchantment that player controls.

Whenever you cast a spell from anywhere other than your hand, put a +1/+1 counter on Ruthless Advisor.
Surpass {5}{B} ({5}{B}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Whenever you cast a spell from anywhere other than your hand, return Ruthless Bakhtak from your graveyard to your hand.

First strike
Ruthless Blademaster gets +1/+0 for each Equipment attached to it.

Whenever another creature with power 4 or greater you control attacks, Ruthless Brawler deals 1 damage to defending player.

When Ruthless Conscript dies, arm up to two target creatures you control. (Create a colorless Equipment artifact token with “Equipped creature gets +1/+0” and equip {2}, then attach it to that creature.)

Whenever you cast a spell that's red, green, white, or blue, each opponent loses 1 life and you gain 1 life.

{2}{R}: Ruthless Mastiff gets +3/+0 until end of turn.

{2}, Remove a counter from another permanent you control: Ruthless Monstrosity gets +2/+2 until end of turn.

Alpha (You may have this creature enter with a +1/+1 counter on it. If you do, it becomes alpha and can only attack alone.)
Ruthless Predator can't be blocked by more than one creature.

{T}, Sacrifice a creature: Conjure a card named Data-Point into your hand. Activate only as a sorcery. (It's a sorcery that costs {2} with “Draw a card.”)

Menace
Ward—Pay 3 life.
Whenever you cast a spell from anywhere other than your hand, each opponent loses 1 life and you gain 1 life.