msem-instigator

When Relentless Toqui enters, put two +1/+1 counters on a creature you control.
Creatures you control with counters on them have haste and menace.

Vigilance
Whenever you cast an artifact spell, put a +1/+1 counter on Relitian Sentry.
Equipped creatures you control get +1/+1 and have first strike.

Trample, haste
When Relonche Cavalry enters, other creatures you control get +1/+0 and gain trample and haste until end of turn.

Remarkable Hunter must be blocked if able.

When Remembrance of Light enters, you may return target permanent card from your graveyard to your hand.
Revive—{4}{G}, Discard a card. ({4}{G}, Discard a card, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Renegade Spellweaver can't be blocked as long as you've foretold a card or cast a foretold spell this turn.

When Renili, Telenian Weaponist enters, you may exile another target creature until Renili leaves the battlefield.
When Renili leaves the battlefield, put a +1/+1 counter on each creature you control.

Flash
If a player would conjure a card, they instead conjure a card named Data-Point. (It's a sorcery that costs {2} with “Draw a card.”.)
If a player would copy a spell or cast a copy, they copy the card named Data-Point instead of anything else.

When Reprising Bard enters, exile target instant or sorcery card with mana value 3 or less from your graveyard. When Reprising Bard is no longer on the battlefield, copy the exiled card. You may cast the copy without paying its mana cost.

Lifelink
Whenever another creature you control with a counter on it dies, return it to its owner's hand. If that creature was an Avatar, return it to the battlefield under your control instead.

Flash
Whenever you cast a Tale, look at the top two cards of your library. Put one into your hand and the other back on top or into your graveyard.

Enspirit (As you cast this spell, you may exile a nonenchantment creature you control until this leaves the battlefield or fails to resolve. Reduce this spell's cost by the exiled card's mana value.)
When Returned Bokor dies, return it to its owner's hand.

At the beginning of your upkeep, if a library has twenty or fewer cards left in it, return Returned Explorer from your graveyard to the battlefield tapped.

As long as there are three or more creature cards in your graveyard, Returned Minotaur gets +1/+1 and has menace.

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Menace
Revive {3}{B} ({3}{B}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Flying
Whenever Revived Pterosaur deals combat damage to an opponent, that player discards a card.
{4}{B}{B}, Discard two cards: Return Revived Pterosaur from your graveyard to the battlefield tapped.

Deploy 4 (As this enters, you may tap any number of other creatures you control with total power 4 or more.)
When Revolutionary Recruiters enters deployed, gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.

Ward {2}
When Rewriter of Flesh enters, target creature you control becomes an enchantment and loses all other card types. (It still has its abilities, but it's no longer a creature.)

Prowess

First strike
Creatures you control attacking cause abilities of that creature to trigger as though it entered.

Flying, menace
When Riftkeeper Entity enters, discard your hand, then draw cards equal to the number of differently named lands you control.
{1}{R}, Discard Riftkeeper Entity: Create a tapped colorless land token named Fading Rift with “{T}, Sacrifice this land: Add one mana of any color.”

First strike
Engage (This creature must be blocked each combat if able.)

Trample
Risti Assault Squadron can't attack unless all other creatures you control also attack. (It can attack if it's the only creature you control.)