msem-instigator

Other Warriors you control have first strike.
Other Barbarians you control get +1/+0.

First strike (This creature deals combat damage before creatures without first strike.)
Other Soldier creatures you control get +1/+1 and have first strike.
{3}{W}: Create a 1/1 white Soldier creature token.

Wither (This deals damage to creatures in the form of -1/-1 counters.)
Whenever Barrow Banshee deals combat damage to an opponent, that player discards a card at random.

Flying, first strike, vigilance, lifelink
When Bastion Valkyrie dies, create three Function tokens with “Choose a creature targeted by this spell. It gains flying, first strike, vigilance, and lifelink until end of turn.” (They're enchantments. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

When Bastion Warden enters, exile target creature an opponent control until target enchantment you control leaves the battlefield.

Renown 2 (When this creature deals combat damage to a player, if it isn't renowned, put two +1/+1 counters on it and it becomes renowned.)
Whenever a creature you control becomes renowned, draw a card.

Flying
When Battlefront Scavenger enters, return target creature card with mana value 3 or less from your graveyard to your hand.

Concord — When Bazaar Equestrian enters, if there are four or more card types among permanents you control, you gain 4 life.

Whenever Bazaar Informant deals combat damage to a player, reveal the top card of that player's library. If it's a nonland card, put a +1/+1 counter on Bazaar Informant, then that player puts that card into their graveyard.

If you would catalyze, catalyze twice instead. (The next spell you cast this turn costs {1} less to cast.)
You may pay an additional {2} as you cast a spell. If you do, reveal the bottom card of your library. You may put it into your graveyard or on top of your library.

When Bearer of Silk Chains enters, gain control of target nonland permanent until Bearer of Silk Chains leaves the battlefield. If that permanent is a Horror, gain control of it instead.

Inspired — Whenever Bearer of Vile Incense becomes untapped, create a 0/1 black Cultist creature token with “{1}{B}{B}, Sacrifice three Cultists: Create a 5/5 black Demon creature token.”

When Bearer of the Lantern enters, you gain 3 life.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Auras and Equipment you control have indestructible.
Whenever Bearidge Marshall attacks, you may create a white Aura enchantment token named Arrest attached to target creature. It has enchant creature and “Enchanted creature can't attack or block, and its activated abilities can't be activated.”

Desecrate (When this creature enters, you may sacrifice an artifact or land.)
When Beastback Raider desecrates a permanent, discard your hand, then draw three cards.

Sleight (You may cast this spell as though it had flash if you pay {1} more to cast it.)
Search your library for a green creature card with mana value X or less, put it onto the battlefield, then shuffle.

If you control ten or more nonland permanents, you get an emblem with “At the beginning of your end step, return target permanent card from your graveyard to the battlefield.”
Destroy all nonland permanents.

Bedfellow can't block or be blocked.
Exile two cards from your graveyard: Bedfellow gets +1/+1 until end of turn.

Concord — When Beetleback Forager enters, if there are four or more card types among permanents you control, return target card from your graveyard to your hand.

All creatures that aren't embattled get -5/-5 until end of turn. If a creature would die this turn, exile it instead. (A creature is embattled if it has a counter on it or a permanent its owner controls attached to it.)

When Belief in the World enters, you may tap two untapped creatures you control. If you do or you control two or more Spirits, search your library for a Spirit card, reveal it, put it into your hand, then shuffle.
Creatures you control get +1/+1.

Enchant creature you control
Enchanted creature gets +3/+3.
When Belligerence enters, enchanted creature fights target creature an opponent controls.
When enchanted creature dies, if it's a Warrior, return Belligerence to its owner's hand.

Trample
Whenever Belligerent's Augur or another Warrior you control deals combat damage to a player, you may pay {1}{U}. If you do, draw a card.

Reprise {4}{G} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)
Target creature gets +3/+3 until end of turn. Then create an X/X green Elk creature token, where X is the amount this spell increased that creature's power.

[+1]: Creatures you control get +1/+0 and gain haste until end of turn.
[0]: Bennett Brooks deals 2 damage to each opponent. If you have an insight counter, create two Treasure tokens.
[0]: You get an insight counter.
[–2]: Sacrifice an artifact. If you do, return target artifact card from your graveyard to the battlefield.