msem-instigator

As an additional cost to cast this spell, remove X +1/+1 counters from among creatures you control.
Create X 2/2 green Wolf creature tokens.

Create two tapped colorless land tokens named Far-Off Lands with “{T}: Add one mana of any color.” (Then exile this card. You may cast the creature later from exile.)

Enchant creature
Converge — When Big Enough enters, put X +1/+1 counters on enchanted creature, where X is number of colors of mana spent to cast Big Enough.
Enchanted creature has trample.

When Big Rock enters, it deals 2 damage to any target.
{T}: Add {C}.
{T}, Sacrifice Big Rock: It deals 2 damage to any target. Activate this ability only if you control a Giant.

Pressure {2}{G} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
As an additional cost to cast this spell, sacrifice a creature.
Search your library for a creature card with mana value X or less, where X is equal to twice the sacrificed creature's mana value, put it onto the battlefield, then shuffle.

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

Until end of turn, cards in graveyards lose all names, card types, and abilities.
Draw a card.

When Bio-Sequencer enters, conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)
{1}, {T}, Sacrifice Bio-Sequencer: Add one mana of any color.

{T}: Add one mana of any color a basic land you control could produce.

When Bioluminescent Predator dies, draw a card, then you may put a land card from your hand onto the battlefield.

When Bird Call enters, search your library for a creature card, reveal it, shuffle, then put that card on top.
{2}, {T}: Target creature gets +1/+1 until end of turn.

Whenever Birthing Elemental or another nontoken creature you control dies, create a 1/1 green Saproling creature token.

Menace
When Bit Player dies, it deals 1 damage to each opponent.

Destroy target creature with flying.

At the beginning of your upkeep, exile the top card of your library. If a land card is exiled this way, add {R}{R}. You don't lose this mana as steps and phases end this turn. Otherwise, you may cast that card this turn.

Bjarndyr Bruiser gets +2/+2 as long as it's embattled. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Trample
Other Bears you control get +2/+2.

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

When Blackwall's Edge enters, if you control four or more lands, you may have each player conjure a card named Data-Point into their hand. (It's a sorcery that costs {2} with “Draw a card.”)
{T}: Add {C}.
When Blackwall's Edge is destroyed, return it to its owner's hand.

Equipped creature gets +3/+1.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

Engage (This creature must be blocked each combat if able.)
Whenever Blade of Fretport becomes blocked by a creature, Blade of Fretport deals 1 damage to that creature.

Flash
When Blade of Mautakesh enters, creatures you control gain poisonous 1 until end of turn. (Whenever those creatures deal combat damage to a player, that player gets a poison counter. Multiple instances of poisonous trigger separately.)

Double strike
Attain {3}{R} ({3}{R}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

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}