msem-instigator

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

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

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

Blessed Grounds enters tapped. When it enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {G} or {W}.

({T}: Add {W} or {B}.)
As Blessed Mausoleum enters, you may pay {1}. If you don't, Blessed Mausoleum enters tapped.

{T}: Add {B} or {G}.
{B}{G}, {T}: Target creature gets +1/+1 until end of turn.

Equipped creature gets +2/-1.
Equip {1}

Flying
Blind Eternal can't be blocked by creatures with mana value 2 or less.
{3}, Discard Blind Eternal: Search your library for a noncreature card with a mana ability, reveal it, put it into your hand, then shuffle. Activate only as a sorcery.

{T}: Add {C}.
Dominance — {1}, {T}: Blistering Boneyard deals 1 damage to each opponent. Activate only if you control the creature with the greatest power or tied for the greatest power.

Whenever equipped creature attacks, choose target creature defending player controls. Destroy that creature at end of combat.
Equip {4}

Bloodfell Caves enters tapped.
When Bloodfell Caves enters, you gain 1 life.
{T}: Add {B} or {R}.

Equipped creature gets +1/+1 and has lifelink.
Whenever equipped creature dies, if it wasn't a token, you may pay {3}. If you do, create a token that's a copy of that creature and attach Bloodguard's Hand to it.
Equip {3}

({T}: Add {R}.)
Bloodriver enters tapped.
When Bloodriver enters, target creature you control gains haste until end of turn.

Bloodsand Gulch enters tapped unless you control another Desert.
{T}: Add {B} or {R}.

{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.

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.)

Bloodstone Halls enters tapped unless you control two or more black and/or red permanents.
{T}: Add {B} or {R}.

Blooming Needles enters tapped unless you control another Desert.
{T}: Add {R} or {G}.

Blooming Vista enters tapped.
{T}: Add {R} or {G}.
{1}, {T}: Add one mana of any color.

When Blossoming Expanse enters, you may put a basic land card from your hand onto the battlefield tapped.
{1}, {T}: Add one mana of any color.

Blossoming Sands enters tapped.
When Blossoming Sands enters, you gain 1 life.
{T}: Add {G} or {W}.

{T}: Add {C}.
{3}, {T}: Draw a card. Spend only mana produced by basic lands to activate this ability.

Trample
{T}: Add {C}.
At the beginning of your upkeep, you may pay {2}. When you do, Blundering Clocktower becomes a creature in addition to its other types until the beginning of your next end step. End the turn.

First strike
Whenever Bodyless Knight attacks, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Bogchomper Juggernaut attacks each combat if able.
Bogchomper Juggernaut can't be blocked by Fungus, Saprolings, Plants, or Insects.