msem-instigator

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
When Budding Companion has three or more +1/+1 counters on it, remove them all and transform it.

First strike
Ascend {1}{B} ({1}{B}: Exile this creature, then return it to the battlefield transformed. Ascend only as a sorcery.)

Exile the top card of your library. You may play that card until the end of your next turn.

Whenever Burning Hart deals combat damage to a player, it deals that much damage to up to one target planeswalker that player controls.

Search your library for a card, put it into your graveyard, then shuffle. (Then exile this card. You may cast the creature later from exile.)

Butcher deals 3 damage to target player. (Cast a copy of this spell once while this creature is on the battlefield.)

This spell can't be countered.
Search your library for a basic land or a Hydra card not named Aurora Hydra, reveal it, and put it into your hand. Then shuffle.

Search your library for a Dragon card, reveal it, put it into your hand, then shuffle. It deals damage equal to its power to you.

Ascend—{W}{B}, Discard a card, Sacrifice a creature, Exile a creature card from your graveyard. ({W}{B}, Discard a card, Sacrifice a creature, Exile a creature card from your graveyard: Exile this creature, then return it to the battlefield transformed. Ascend only as a sorcery.)

Vigilance
Unveil {2}{G}{W} ({2}{G}{W}: Transform this. Unveil only as a sorcery.)

Until end of turn, all creatures gain deathtouch and “When this creature dies, its controller loses 2 life.”

Equipped creature gets +1/+1 for each differently named land you control.
Equip {3}

Return target tapped creature to its owner's hand. (Then exile this card. You may cast the creature later from exile.)

Whenever Cattish Bluestocking deals combat damage to a player, draw a card.
Attain {4}{U} ({4}{U}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

When Cave Eel enters, look at the top three cards of your library. Put one on top and the rest on the bottom in any order.

First strike
Whenever a creature blocks Celestial Conscript, put a -1/-1 counter on that creature.

Flash
When Cephalovorous Flukes enters, counter target spell or ability that targets you or a permanent you control.

Legacy (You may play this side of this card only from your graveyard. Exile it if it would be put into a graveyard or not resolve.)
Shuffle any number of target cards in graveyards into their owners' libraries.
Scry 2, then you gain 3 life.

At the beginning of your upkeep, each opponent loses 1 life and you gain 1 life.

Target creature gets +2/-2 until end of turn. (Then exile this card. You may cast the artifact later from exile.)

Trample
Whenever Charging Cassowary deals combat damage to a player, you may cast a copy of an Adventure of a permanent you control.

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
When Cheerful Generator has three or more +1/+1 counters on it, remove them all and transform it.

{1}, Sacrifice a creature: Put a +1/+1 counter on Chitterrax, then each opponent loses 1 life and you gain 1 life.

Haste
Claret Gorger can't block.
Unveil {2}{B}{R} ({2}{B}{R}: Transform this. Unveil only as a sorcery.)

Whenever a creature enters under an opponent's control, you may have that player lose 1 life.
Unveil {2}{B}{R} ({2}{B}{R}: Transform this. Unveil only as a sorcery.)