msem-instigator

Blighted Unicorn can't block.
Ride {3}{B} ({3}{B}: Transform this and attach it to target creature you control without a Steed. Ride only as a sorcery.)

When Blinding Fiddler enters, until your next turn, creatures can't attack you or a planeswalker you control unless their controller pays {2} for each of those creatures.
Unveil {3}{W}{U} ({3}{W}{U}: Transform this. Unveil only as a sorcery.)

Whenever Blood Constrictor becomes blocked by a creature, you gain life equal to that creature's toughness.

Destroy target creature that was dealt damage this turn. (Then exile this card. You may cast the creature later from exile.)

Flying, menace
Sacrifice a creature: Put two +1/+1 counters on Bloodclaw Demon. It gains indestructible until end of turn.

Flying
{1}, Sacrifice a creature: Put a +1/+1 counter on Bloodthirsty Manticore. It gains indestructible until end of turn. Tap it.
Surpass {4}{B}{R} ({4}{B}{R}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Deathtouch

You may cast a spell with mana value 3 or less from your hand without paying its mana cost. (Then exile this card. You may cast the creature later from exile.)

[+1]: Boxue deals 1 damage to each opponent. You may draw a card, then discard a card.
[–1]: Create a Treasure token.
[–5]: Copy the next spell you cast this turn. You may choose new targets for the copy. (A copied permanent spell becomes a token.)

Target opponent discards two cards. (Cast a copy of this spell once while this creature is on the battlefield.)

Gain control of target permanent. (Cast a copy of this spell once while this creature is on the battlefield.)

Wither (This deals damage to creatures in the form of -1/-1 counters.)
When you unveil Bramble Quickling, you may have it fight target creature.

Sacrifice another creature: Brash Hunter deals 1 damage to any target.
At the beginning of your end step, if three or more creatures died this turn, transform Brash Hunter.

Double your life total. (Then exile this card. You may cast the creature later from exile.)

Prowess
Unveil {2}{U}{R} ({2}{U}{R}: Transform this. Unveil only as a sorcery.)

Prowess, trample
Whenever Brilliant Diviner deals combat damage to a player, draw a card.

{2}{R}: Target creature can't block Brimstone Courser this turn.
Ride {3}{R}{R} ({3}{R}{R}: Transform this and attach it to target creature you control without a Steed. Ride only as a sorcery.)

Whenever Brine Kelpie attacks, you may tap target creature an opponent controls.
Ride {2}{U} ({2}{U}: Transform this and attach it to target creature you control without a Steed. Ride only as a sorcery.)

Create two 1/1 green Insect creature tokens. (Cast a copy of this spell once while this creature is on the battlefield.)

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.)