msem-instigator

Target creature gets +1/+1 until end of turn for each card in your graveyard.

{1}, {T}, Pay 1 life: Put a +1/+1 counter on target creature you control.
{T}, Remove a counter from a permanent you control: Draw a card.

{2}, {T}, Sacrifice a creature: You draw a card and you lose 2 life.
{1}, {T}, Exile a creature card from your graveyard: You gain 2 life.

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.

Equipped creature gets +1/+1 for each charge counter on Bloodstained Knife.
{2}, Sacrifice a creature: Put a charge counter on Bloodstained Knife.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Flying, deathtouch
When Bloodsucking Pihuchen enters the battlefield, choose a nonland card name.
Whenever a permanent with the chosen name enters the battlefield, each opponent loses 1 life and you gain 1 life.

{T}: Another target Warrior you control gets +1/+0 and gains haste until end of turn.

Whenever Bloodthirsty Insurgent attacks, it gets +2/+0 until end of turn.

Target creature gets +3/+2 and gains trample until end of turn.

At the beginning of each player's end step, if they aren't horrific, Bloody Valentine deals 2 damage to that player. (You're horrific as long as you've sacrificed a permanent or discarded a card this turn.)

Reach
{1}{B}: Bloomcrawler gains deathtouch until end of turn.

Look at the top four cards of your library. You may reveal a permanent card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Destroy target artifact or enchantment. If that permanent was a token, proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

When Blossom-Sower Witch enters the battlefield, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
Whenever you sacrifice a permanent, you gain 1 life.

Whenever another creature enters the battlefield under your control, you may have it gain haste. If you do, return it to its owner's hand at the beginning of the next end step.

Menace
When Bogborn Exorcist enters the battlefield, you may discard a card. When you do, exile target instant or sorcery card with mana value 3 or less from an opponent's graveyard. Copy that card. You may cast the copy without paying its mana cost.

Enchant creature
When enchanted creature dies, return that card to the battlefield under your control.

Damage can't be prevented.
At the beginning of your upkeep, Bomb Juggler deals 3 damage to target player chosen at random.

Assault {1}{B} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
When Bone Mesa Marauder assaults, it gains flying until end of turn.

When Bone Pit Raptor enters the battlefield, other creatures you control get +1/-1 until end of turn.
Revive {2}{R} ({2}{R}, 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.)

Paranoia—Exile a creature card from your graveyard. (You may cast this spell for its paranoia cost when a permanent you control leaves the battlefield.)
Equipped creature gets +2/+0.
Equip {1}

As long as an opponent has two or fewer cards in their hand, Bonespitting Monstrosity gets +2/+2 and has menace and “Whenever Bonespitting Monstrosity attacks and isn't blocked, create a 1/1 black Skeleton creature token.”

Return target nonland permanent you control and target nonland permanent you don't control to their owners' hands.

Whenever a creature you control deals combat damage to a player, you may sacrifice it. If you do, draw cards equal to that creature's power.

{2}, Sacrifice Bottled Fate: Put the top card and bottom card of your library into your hand.