msem-instigator

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.

Lifelink
When Bastion Chaplain enters the battlefield, create two Function tokens with “Lifelink.” (They're enchantments. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

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 the battlefield, exile target creature an opponent control until target enchantment you control leaves the battlefield.

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast enchantment spells or to activate an ability of an enchantment.
When Bastion, Node of the Free is destroyed, return it to its owner's hand.

Creatures you control have “{T}: Add {C}.”
Mirage {1}{U} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

Enchant creature
Enchanted creature gets -2/-0.
{3}{U}{U}: Submerge enchanted creature. (To submerge a card, exile it, then put it on the battlefield face down under its owner's control as a 2/2 creature.)

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.

(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.

As Battle for the Shield enters the battlefield, choose Danuri or Fellor.
• Danuri — Soldiers you control get +0/+1 and have vigilance.
• Fellor — Warriors you control get +1/+0 and have first strike.

At the beginning of your upkeep, you may discard a card. If you do or if you control a creature with power 4 or greater, draw a card.

As Battle the Evil One enters the battlefield, choose Evil One or Rehison.
• Evil One — Zombie creature cards in your graveyard have unearth {3}{B}.
• Rehison — Whenever an Elf enters the battlefield under your control, you may put a -1/-1 counter on target creature.

When Battlemage's Disruption enters the battlefield, you may return target creature to its owner's hand.
{3}{U}, Sacrifice Battlemage's Disruption: Return target creature to its owner's hand.

Whenever one or more creatures you control attack, you may put a progress counter on Battlesuit Prototyping.
[PROGRESS 2-6] Creatures you control get +1/+1.
[PROGRESS 7+] Creatures you control get +2/+2 and have indestructible.

Enchant creature (Target a creature as you cast this. This card enters the battlefield attached to that creature.)
Enchanted creature gets +2/+2 and has first strike and vigilance.

First strike
Whenever you scry, Battlewise Paragon gets +1/+1 until end of turn for each card you looked at while scrying this way.

(Transform this if it's not attached to a creature. Pay {1}{U} as a sorcery to unattach it.)
Enchant creature you control
Bay-Bandit's Snapper's rider gets +1/+2.
Whenever Bay-Bandit's Snapper's rider deals combat damage to a player, you draw two cards.

Enchant creature
Enchanted creature gets +1/+1.
Sacrifice Bear Necessities: Enchanted creature gains indestructible until end of turn.

Enchant creature
Enchanted creature has base power and toughness 8/8.

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.

Sabotage — Whenever an opponent or permanent an opponent controls becomes the target of a spell you control, put a quest counter on Beckon Darkness.
At the beginning of your upkeep, if Beckon Darkness has four or more quest counters on it, return target creature card from your graveyard to the battlefield.

Insects you control have hexproof.
At the beginning of your end step, if you control a nontoken Insect, create a 1/1 green Insect creature token.

Enchant creature
Enchanted creature gets +1/+1 and has vigilance.
{2}{G}: Return Behold the Horizon from your graveyard to your hand.

Enchant creature
Enchanted creature has base power and toughness 1/1 and is a Frog in addition to its other types.
When enchanted creature deals damage to a player, sacrifice Belittle.

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