msem-instigator

Protection from multicolored
[+2]: Create a colorless artifact token named Mind Stone with “{T}: Add {C}” and “{1}, {T}, Sacrifice Mind Stone: Draw a card.”
[–3]: Create Barxbot 9000, a legendary 6/4 colorless Construct artifact creature token with “All damage that would be dealt to Barx planeswalkers you control is dealt to this creature instead.”
[–12]: You and target opponent each gain control of each permanent the other controls that's one or more colors.

As an additional cost to cast this spell, exile a noncreature artifact you control with mana value X until Barx leaves the battlefield or fails to resolve. X can't be 0.
[+1]: Exile the top card of your library. You may play it until you exile another card with Barx.
[–3]: Create an X/X colorless Hound artifact creature token, where X is the greatest mana value among cards exiled by Barx.
[–10]: Search each player's library for any number of nonland cards with total mana value 10 or less and exile them, then those players shuffle. Cast those cards without paying their mana costs.

Batrest, Fellor Leader gets +1/+1 for each Equipment attached to it.
When Batrest enters the battlefield, create Astrina, Forged for Glory, a legendary colorless Equipment artifact token with “Equipped creature gets +4/+4 and has first strike and lifelink” and equip {4}. Attach it to Batrest.

Equipped creature gets +1/+1.
As long as equipped creature is a Soldier or Warrior, it gets an additional +1/+1.
Equip {1}

{4}{G}: Battle Station gets +3/+3 until end of turn.
Cycling {2/G} ({2/G}, Discard this card: Draw a card.)

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Reveal the top four cards of your library. Put a creature card with mana value 4 or less from among them onto the battlefield and the rest into your graveyard.
II — Any number of target creatures you control fight target creature you don't control.
III — Put up to three target cards from your graveyard on top of your library in any order.

At the beginning of your upkeep, Bauble of Infinites deals 2 damage to each opponent and you gain 2 life.

Flash
Haste
{3}, {T}: Exchange control of two target noncreature spells. Their controllers may choose new targets for the spells.

When Bearer of Old Growth enters the battlefield, choose one —
• Untap up to two target artifacts.
• Draw a card.

Equipped creature has menace and trample.
Equip {2}

Menace
When Beatrice enters, target opponent reveals their hand. Exile a nonland card from it. During any turn that player lost life, you may cast that card and mana of any type can be spent to cast that spell.

{T}: Add one mana of any color.
{2}, {T}: Put a lore counter on a Saga you control.

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.

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.

{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.

[+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 Big Rock enters the battlefield, 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.

Trample, haste, indestructible
Whenever a permanent an opponent controls is put into a graveyard from the battlefield, put a +1/+1 counter on target Ooze.

Equipped creature gets +1/+1.
Whenever equipped creature becomes blocked, you may pay {1}{W}. If you do, detain each creature blocking it. (Until your next turn, those creatures can't attack or block and its activated abilities can't be activated.)
Equip {2}

When Bio-Sequencer enters the battlefield, 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.

When Biohazard enters the battlefield, destroy all other nonland permanents with mana value X or less.
At the beginning of each end step, each opponent loses life equal to the number of cards they've drawn this turn plus the number of spells they've cast this turn.

When Bird Call enters the battlefield, 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.

Legacy (You may play this side of this card only from your graveyard. Exile it if it would leave the battlefield or not resolve.)
Permanents you control have lifelink and “{T}: Add one mana of any color.”

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