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 as you activate this ability.
[–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.

Whenever you cast an Adventure spell, put a +1/+1 counter on Adventurer Extraordinaire.

Target creature you control gains haste until end of turn. Return it to its owner's hand at the beginning of the next end step.

Flying
As long as Aerial Tactician is tapped, Soldiers you control get +0/+1.
As long as Aerial Tactician is untapped, Soldiers you control get +1/+0.

Menagerie — This spell costs {2} less to cast if there are five or more creature types among creatures you control.
Destroy target creature with power or toughness 4 or greater.

Vigilance
Blessed Suncrusher's power and toughness are each equal to your life total.

Double your life total. (Then exile this card. You may cast the creature later from exile.)

Bristling Skoki has first strike as long as it's attacking.
Whenever Bristling Skoki blocks a creature, you may have it deal damage equal to its toughness to that creature.

{W}, {T}: Target attacking creature gets +1/+1 until end of turn. This ability costs {W} less to activate if it targets a Soldier.

Put a +1/+1 counter on each creature you control. (Then exile this card. You may cast the creature later from exile.)

Whenever Dawn Hill Daybreaker or another creature you control enters, you gain 1 life. If that creature is a Cleric, tap up to one target creature an opponent controls.

Double strike

Search your library for an Equipment card, reveal it, put it into your hand, then shuffle. (Then exile this card. You may cast the creature later from exile.)

Vigilance
This spell costs {1} less to cast for each +1/+1 counter among creatures you control.

Put a +1/+1 counter on each creature you control that entered this turn. (Then exile this card. You may cast the creature later from exile.)

Untapped creatures you control get +1/+1.
Soldiers you control have vigilance.

Lifelink
Frostguard Sentry has flying as long as it has a +1/+1 counter on it.

Flying
Whenever you cast a creature spell, creatures you control get +1/+1 until end of turn.
Whenever you cast a noncreature spell, create a 2/2 red and white Cat Knight creature token.

When Happily Retired enters, exile target creature you don't control with mana value 3 or less until Happily Retired leaves the battlefield.
{1}, Sacrifice Happily Retired: Return target exiled creature card you own that's on an Adventure to your hand. Activate only as a sorcery.

Flying, lifelink

Target creature you control gains protection from the color of your choice until end of turn. (Then exile this card. You may cast the creature later from exile.)

This spell costs {1} less to cast for each +1/+1 counter among creatures you control.
Hoof Cliff Heartminer enters with four +1/+1 counters on it.
Whenever Hoof Cliff Heartminer or another creature you control leaves the battlefield, you may put its +1/+1 counters on another target creature you control.

Vigilance
Menagerie — When Hoof Cliff Trihorn enters, if there are five or more creature types among creatures you control, you may search your library for a card named Hoof Cliff Trihorn, reveal it, put it into your hand, then shuffle.

When Karoa's Faithful enters, target creature gets +X/+X until end of turn, where X is the total number of creatures you control that are Knights or have Adventures.

Vigilance
Whenever Karoa's Vanguard or another Knight you control enters, if an opponent controls more lands than you, you may search your library for a Plains card, reveal it, put it into your hand, then shuffle.