msem-instigator

When Roseblood Hart enters, choose one —
• Destroy target artifact.
• Create a Treasure token.

Instant, sorcery, and enchantment spells you cast cost {1} less to cast.

Prowess
When Rosebud Runner enters, exile the top card of your library. During your next turn, you may play that card from exile.

({T}: Add {R}.)
Rousing Rubble enters tapped.
Double strike
{2}{R}{R}: Rousing Rubble becomes a creature in addition to its other types until end of turn.

Whenever Roving Dreadnought attacks, you may salvage a card that was put into your graveyard this turn. (Exile one from your graveyard until this creature leaves the battlefield. Whenever this creature deals combat damage to a player, put a card it salvaged into your hand.)

Gain control of up to two target creatures until end of turn. Untap them. They gain haste until end of turn.
Menagerie — If there are five or more creature types among creatures you control, untap all creatures you control. Until end of turn, they gain “{T}: This creature fights another target creature.”

When Royal Retriever enters or when a creature you control scavenges it, you may discard a card. If you do, draw a card.
Scavenge {R} ({R}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Flying
Whenever Rubble Scavenger deals combat damage to a player, you may return target artifact card with mana value 4 or less from your graveyard to the battlefield.

When Rubble Seer enters, you may sacrifice a land or exile a land card from your graveyard. If you do, exile the top card of your library. Until the end of your next turn, you may play that card.

Choose target creature, then choose two —
• The chosen creature gets +3/+0 until end of turn.
• The chosen creature gains trample until end of turn.
• The chosen creature gains first strike until end of turn.

Haste
Ruin Shark attacks each turn if able.
Ruin Shark gets +1/+0 and has first strike as long as you've drawn two or more cards this turn.

{1}, Sacrifice Ruinous Proselyte: Destroy target artifact or nonbasic land.

At the beginning of your end step, Run & Gun deals damage to each opponent equal to the number of tapped creatures you control.

Whenever a creature or planeswalker enters under an opponent's control, sacrifice Rune-Scribe's Trap unless you pay {R}. If you sacrifice it, it deals 6 damage to that permanent.

Enchant creature
Enchanted creature gets +3/+0 and has menace.
Whenever enchanted creature deals combat damage to a player, discard a card, then draw a card.

Discard a card, draw a card, then conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

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.

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

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

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.