msem-instigator

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}

Equipped creature gets +1/+1 and has haste.
Whenever a creature you control enters, if it was cast from exile, you may attach Blade of the Valiant to it.
Equip {2}

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.)

Equipped creature gets +2/+0.
Equip {1}

Invigorate X, where X is the number of creatures you control. (Choose a creature with the least power among creatures you control and put X +1/+1 counters on it.)

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

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

When Blazeblade Sergeant enters, adjudicate. (Create a white Aura enchantment token with enchant creature and “Sacrifice this token: Untap enchanted creature” attached to target creature.)
Whenever an Aura you control enters, target creature you control gains first strike until end of turn.

Trample

Blazing Beam deals 4 damage to any target.

Blazing Exultation deals 3 damage to any target.
{2}{R}: Shuffle Blazing Exultation and up to one other instant or sorcery card from your graveyard into your library.

Trample, haste
When Blazing Fox enters, you may tap an untapped creature you control. If you do, Blazing Fox gets +X/+0 until end of turn, where X is that creature's power.