msem-instigator

Destroy target artifact or land.

You may have Blurry Counterpart enter as a copy of any creature on the battlefield.
Mirage {1}{U} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

Create three 1/1 blue and red Pirate creature tokens with haste.

Target creature you don't control fights target creature you control, then fights up to one other target creature you don't control.

Haste
Augmented — Whenever you cast a spell, if you've spent {W}{U}{B}{R}{G} to cast spells this turn, put a +1/+1 counter on Bolstered Guardian. It loses this ability and gains “Whenever this attacks, it deals 2 damage to each of up to two targets.”

Each creature you control gets +1/+1 for each permanent attached to it.

When Boneweary Warrior dies, you may put a -1/-1 counter on target creature.

Your life total becomes 20.
Coalesce {8}{W}{W}{W}{W} (You may cast this from your graveyard for {8}{W}{W}{W}{W}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
Born Anew's power and toughness are each equal to your life total.

Bound by Nature enters with X nature counters on it.
You can't cast nonpermanent spells.
Creatures you control get +1/+1 for each nature counter on Bound by Nature and have “{T}: Add {G}.”

For each creature token you control, create a token that's a copy of that creature.

Flying
Whenever you attack, another target creature you control gains flying until end of turn.
Fleeting {U} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

Gain control of target nonland permanent you don't control unless its controller has Bow or Burn deal X damage to them, where X is twice that permanent's mana value. If Bow or Burn was cast from a graveyard, repeat this process for each other nonland permanent they control.
Flashback {6}{R}{R}

When Braenid Nomad enters, draw two cards, then discard a card.

Counter target spell. Spells its controller casts cost {2} more to cast this turn.

If you would draw a card, instead exile the top three cards of your library face down. You may look at those cards. Put a card exiled with Brainstorming Session into its owner's hand.
{X}{X}{U}, Sacrifice Brainstorming Session: Put X cards exiled with it into their owner's hand.

As Brave the Issbarrens enters, choose a color.
White creatures you control have protection from the chosen color. (This permanent can't be targeted, dealt damage, enchanted, or equipped by anything with that color.)

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.)
Brazen Chimera can't be blocked except by three or more creatures as long as it has a +1/+1 counter on it.

Put a number of +1/+1 counters on target creature you control equal to that creature's power.
Spell mastery — If there are two or more instant or sorcery cards in your graveyard, you may have that creature fight another target creature. (Each deals damage equal to its power to the other.)

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

Flying, trample
Whenever Bretala of Redsky attacks, it gains double strike until end of turn unless defending player sacrifices a creature.

Hexproof
Whenever attackers are declared, the active player may pay {2} for each creature attacking you. Then you may have Bridge Kalak become an X/X Troll creature until end of turn, where X is the number of times that player didn't pay mana this way.

Flying
When Brilliant Griffin enters, target creature gets +2/+2 until end of turn.

Flying, vigilance
Protection from Humans (This creature can't be blocked, targeted or dealt damage by Humans.)

At the beginning of your upkeep, you may discard a land card. When you do, create a 2/2 green Wolf creature token.

Target player draws seven cards, then their life total becomes equal to the number of cards in their hand.