msem-instigator

This spell can't be countered.
Whenever Bitter Leviathan becomes the target of a spell or ability, exile it. Return it to the battlefield under your control tapped and attacking at the beginning of the declare attackers step on your next turn. It can't be blocked that combat.

When Bitter Pact enters the battlefield, destroy target nonbasic permanent.
All permanents and players lose hexproof, indestructible, and protection and can't have or gain hexproof, indestructible, or protection.

Return to your hand all permanent cards in your graveyard that were put there from the battlefield this turn.

Lifelink
Whenever Bjarndyr Sergeant attacks, other creatures you control get +1/+1 and gain lifelink until end of turn.

You lose 1 life and exile the top card of your library. You may repeat this process any number of times. Then put up to two cards exiled this way into your hand.
Coalesce {5}{B}{B} (You may cast this from your graveyard for its coalesce cost. If you do, put it onto the battlefield as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
Black Hole Musings's power is equal to the number of cards in exile.

Equipped creature gets +4/+2 and has first strike, vigilance, and trample.
Equip {3}

Flying
Whenever Blade of Reckoning deals combat damage to a player, that player sacrifices an untapped permanent.

Blade of the Many can be attached only to a nonlegendary creature.
Equipped creature gets +2/+2.
Each other creature you own is a copy of equipped creature.
Effects that would cause permanents you own to become creatures cause them to become copies of equipped creature instead.
Equip {6}

Exile target instant or sorcery card from your graveyard. Copy it. You may cast the copy. (Cast a copy of this spell once while this creature is on the battlefield.)

If a player would mill one or more cards, they mill that many cards plus two instead.

Advance {1}{R}{W}{B} (Cast this for {1}{R}{W}{B} to advance it as it enters. {1}{R}{W}{B}: Advance this as a sorcery.)
Whenever Blastburn Angel advances, it gets +1/+1 and gains flying until end of turn. It deals 1 damage to each other creature.

Blazing Outro deals 4 damage to any target. Then you may tap an untapped Wizard you control. If you do, cast an instant or sorcery card with mana value 4 or less from your graveyard without paying its mana cost. If it has X in its mana cost, X is 4. If that spell would be put into a graveyard, exile it instead.

({T}: Add {U}, {B}, or {R}.)
Bleak Dominion enters the battlefield tapped.

Bleak Shoreline enters the battlefield tapped unless you control an Island.
{T}: Add {W} or {B}.

Bleakrealm Moor enters the battlefield tapped unless you played it from exile.
{T}: Add {B} or {R}.

{1}{G}, {T}: You may put a creature or Revelation card from your hand onto the battlefield. Exile that permanent if it would leave the battlefield. If it's a Revelation, it enters the battlefield as a Horror creature and you may cast a copy of it without paying its mana cost.

When Blessed Spellroot dies, you gain 5 life.

Vigilance
Blessed Suncrusher's power and toughness are each equal to your life total.

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
Whenever Blessed Vanquisher encourages a creature, destroy target creature an opponent controls if it's tapped. Otherwise, tap that creature.

At the beginning of your upkeep, create two 1/1 colorless Construct artifact creature tokens, then you gain life equal to the number of artifacts and enchantments you control.

Up to two target creatures you control each get +2/+0 and gain first strike and haste until end of turn.
Orchestrate—Tap an untapped red and white creature you control or an untapped red creature you control and untapped white creature you control. (You may exile this card from your hand anytime you could cast a sorcery for its orchestrate cost. When you next resolve a spell, you may cast this from exile without paying its mana cost.)

Trample
{1}{G}: Put an overgrowth counter on target creature you control. As long as it has an overgrowth counter on it, it has base power and toughness 8/8.

{1}{B}, {T}: Target creature gets +2/+2 and gains winnow until end of turn. (Damage dealt to it also causes its controller to lose that much life.)
{3}{B}{B}, {T}: Target creature gets -2/-2 and gains winnow until end of turn.

When Blighting Ooze enters the battlefield, put a -1/-1 counter on each of up to X target creatures.
As long as Blighting Ooze is on the battlefield, it has all activated abilities of each creature with a -1/-1 counter on it.

Flash
Blind Blackguard can't block.
When Blind Blackguard enters the battlefield, target player draws a card, then reveals their hand. You choose a nonland card from that player's hand, then that player puts the chosen card on the bottom of their library.