msem-instigator

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

Target creature gets +2/+1 and gains trample until end of turn.

Target creature gets +3/+0 and gains first strike until end of turn.

Exile the top two cards of your library. Until the end of your next turn, you may play those cards. (If you cast a spell this way, you still pay its costs. You can play a land this way only if you have an available land play remaining.)

As an additional cost to cast this spell, put a card from your hand on the bottom of your library.
Draw two cards.

Gain control of target creature until end of turn. Untap that creature. Then create two 1/1 red Satyr creature tokens with “This creature can't block.” Creatures you control gain haste until end of turn.

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

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.

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

{2}{R}: Ruthless Mastiff gets +3/+0 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.”)

If a player taps a nonbasic land for mana, that land produces {C} instead of any other type.
Whenever Rylei Wakebreaker attacks, it and another target creature you control each get +1/+0 until end of turn for each attacking creature you control.

Haste
Whenever an embattled creature you control deals combat damage to a player, you may pay {2}{G}. If you do, create a token that's a copy of that creature, except the token isn't legendary if the creature is legendary. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Whenever S-40 Wallbreaker attacks, create a 1/1 colorless Construct artifact creature token.
{X}, Sacrifice X artifacts: S-40 Wallbreaker deals X damage to each opponent.

Equipped creature gets +2/+0 and can't be blocked.
Whenever a Rogue you control attacks, you may pay {1}. If you do, attach Saber of Defiled Rites to it.
Equip {5}

When Sabne's Autumn enters, search your library for a Forest card, reveal it, put it into your hand, then shuffle. You gain 3 life.
{1}{G}{G}: Transform Sabne's Autumn. Activate only if your fealty to Forests is five or greater.

Indestructible
Lands you control have “{T}: Add {G}{G}.”
{5}{G}{G}: Double the power and toughness of each creature you control until end of turn.

Spells you cast during combat cost {1} less to cast.
Spells your opponents cast during combat cost {1} more to cast.

({T}: Add {W}.)
Sacred Sanctuary enters tapped with two sanctum counters on it.
{T}, Remove a sanctum counter from Sacred Sanctuary: Add {G} or {U}.

Sacred Summits enters tapped.
{T}: Add one mana of any color among the color identity of legendary creatures and planeswalkers you control or legendary cards in your command zone.

{G}: Exile target card from a graveyard. If it was a land card, put a +1/+1 counter on Sacrificial Bull.
{G}, Sacrifice Sacrificial Bull: You gain life equal to its power.

Trample
When Saddlesaur Guide enters, create a green Aura enchantment token named Hefty Load attached to target creature. The token has enchant creature and “Enchanted creature gets +2/+2 and has trample.”