msem-instigator

At the beginning of your upkeep, you may pay 3 life. If you do, create a 2/1 red Lizard creature token with frenzy 2. (Whenever it attacks and isn't blocked, it gets +2/+0 until end of turn.)

Enchant creature
When Bogfume Pact enters, each opponent sacrifices a creature.
When enchanted creature dies, return it to its owner's hand.

Whenever Boghex Witch deals combat damage to a cursed player, that player loses the game.
{2}{B}: Look at the top five cards of your library. You may reveal a Curse card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Flying
When Bogsnatcher Drake enters, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Equipped creature has menace.
Equip {0} ({0}: Attach to target creature you control. Equip only as a sorcery.)

({T}: Add {U} or {R}.)
Boiling Ridge enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

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

Flying, first strike

Whenever Bold Vanquisher attacks, upgrade it. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Trample

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.

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

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
Enchanted creature doesn't untap during its controller's untap step.

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, 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.)

Equipped creature gets +1/+0.
Equip {1} ({1}: Attach to target creature you control. Equip 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}

Whenever another creature you control dies, you may pay {1}. If you do, scry 1. (To scry 1, look at the top card of your library. You may put that card on the bottom of your library.)

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.”

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Sacrifice Bonetooth Darter: Counter target instant, planeswalker, or sorcery spell unless its controller pays {1}.

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

Deathtouch

Boneyard Pass enters tapped unless you control a basic land.
{T}: Add {W} or {B}.

At the beginning of your upkeep, sacrifice a non-Snake creature or Boon of the Pacts. Then create a 1/1 black Snake creature token with deathtouch.
At the beginning of your draw step, draw an additional card.
Spells you cast cost {1} less to cast.