msem-instigator

Flying
When Benevolent Malach enters, create a 1/1 colorless Construct artifact creature token.
Sacrifice Benevolent Malach: Artifacts you control gain indestructible until end of turn.

When Benign Whisper enters, return another target creature to its owner's hand.

[+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.

When Benthic Alchemist enters, draw a card, then discard a card, then mill a card.
Whenever you cast an instant or sorcery spell, create a 1/1 colorless Elemental creature token. It gains haste until end of turn.

When Benthic Shipcrasher enters, scry 3.

{T}: Until end of turn, target land is every basic land type in addition to its other types and its name becomes Morphic Sea.

When Benthic Tidebreaker enters, reveal the top card of each player's library and exile one of those cards. You may play that card for as long as it remains exiled, and you may spend blue mana as though it were mana of any color to cast it.
Evoke {1}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Armed — Beragnian Blacksmith can't attack unless it's equipped.
When Beragnian Blacksmith enters, you may pay {2}. If you do, arm it. (Create a colorless Equipment artifact token with “Equipped creature gets +1/+0” and equip {2}, then attach it to this creature.)

Tap up to two target creatures. They don't untap during their controller's next untap step.
Reprise {3}{U} (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.)

Whenever Beragnian Brawlmaster or another Warrior you control enters, that Warrior fights target creature an opponent controls.
{R}{W}: Target Warrior creature gets +1/+1 until end of turn.

Armed — Whenever Beragnian Intimidator attacks, if it's equipped, target creature can't block this turn.

Armed — Beragnian Savage gets +1/+0 and has first strike as long as it's equipped.

Flying
Sacrifice six Swamps: Return Berbarus Unsealed from your graveyard to the battlefield with an indestructible counter on it. You draw six cards and you lose 6 life.

Target opponent reveals their hand. You choose a nonland permanent card from it. That player discards that card.

Prevent all combat damage that would be dealt to and dealt by Bereaved Aristocrat.
Unveil {2}{W}{U} ({2}{W}{U}: Transform this. Unveil only as a sorcery.)

Whenever equipped creature attacks, it gets +X/+0 until end of turn, where X is its power.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

At the beginning of your upkeep, mill a card.
Whenever a creature card is put into your graveyard from anywhere, if that card has flying, you may put a flying counter on Berylscale Alaj. Repeat this process for first strike, double strike, deathtouch, hexproof, lifelink, menace, reach, trample, and vigilance.

Choose one —
• Target creature gets +2/+0 and gains first strike until end of turn.
• Destroy target artifact.

{1}{G}: Until your next turn, Bessie becomes a 5/5 green Wurm creature with trample, haste, and indestructible. You can't activate this ability while Bessie is being attacked. (She doesn't lose loyalty while she's not a planeswalker.)
[+1]: Creatures you control get +1/+1 and gain haste until your next turn.
[–6]: Create five 3/3 green Wurm creature tokens with trample and haste.

When Bessie's Brood enters, it fights target creature. (If there are no other creatures, it eats itself.)

Trample
Bessie's Crusher has haste as long as you control another Wurm.

[+2]: Create a 3/3 red Wurm creature token.
[–2]: Up to three target creatures each get +2/+2 until end of turn. Bessie deals 2 damage to each of up to three target creatures.
[–9]: You get an emblem with “Creatures you control have base power and toughness 7/7 and have indestructible.”

When a creature you control becomes the target of a spell or ability an opponent controls, sacrifice Bestial Harmony. If you do, draw three cards.

Bestial Mob's power and toughness are each equal to the number of creatures you control.
Whenever Bestial Mob deals combat damage to a player, destroy target creature with toughness less than Bestial Mob's power.

Create a 3/3 green Beast creature token, then populate. (Create a token that's a copy of a creature token you control.)