msem-instigator

Haste
Desecrate (When this creature enters, you may sacrifice an artifact or land.)
When Bloodboil Harlequin desecrates a permanent, up to two target creatures can't block this turn.

Sacrifice another creature: Put a +1/+1 counter on target creature you control. Activate only as a sorcery.

Flying, menace, haste
When Bloodfiend Ravager enters, it deals 2 damage to any target. If a permanent dealt damage this way would die this turn, exile it instead.
Evoke {1}{R} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Flying, haste
{1}{R}{R}: Return Bloodfire Phoenix from your graveyard to the battlefield. Activate only if an opponent lost 3 or more life this turn.

Sacrifice a creature: Put a +1/+1 counter on Bloodlash Caravan. Then if it's the only creature you control, it gains indestructible until end of turn.

This spell costs {1} less to cast for each creature that attacked this turn.

Discard a card: Bloodshot Berserker gets +1/-1 until end of turn. Any player may activate this ability.

Align X (Choose modes with total ★ less than or equal to X. You may choose modes multiple times.)
• ★ — Bloodstained Calamity deals 1 damage to each creature, player, and planeswalker.
• ★★ — Return target instant or sorcery card from your graveyard to your hand. Exile Bloodstained Calamity.
• ★★★★★ — Bloodstained Calamity deals 10 damage to any target.

Menace (This creature can't be blocked except by two or more creatures.)
Cycling {R} ({R}, Discard this card: Draw a card.)

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.)