msem-instigator

Aleud Beastmaster has frenzy X, where X is the number of unblocked attacking creatures you control. (Whenever it attacks and isn't blocked, it gets +X/+0 until end of turn.)

Frenzy 1 (Whenever this creature attacks and isn't blocked, it gets +1/+0 until end of turn.)
Aleud Bladedancer has hexproof as long as it's attacking.

Frenzy 2 (Whenever this creature attacks and isn't blocked, it gets +2/+0 until end of turn.)
Whenever Aleud Blademaster becomes blocked, it gains double strike until end of turn.

Enchant creature
Enchanted creature gets +2/+2 and has hexproof.
Sacrifice Aleud Grace: Enchanted creature gains indestructible until end of turn.

Frenzy 1 (Whenever this creature attacks and isn't blocked, it gets +1/+0 until end of turn.)
Whenever Aleud Pathfinder becomes blocked, untap up to two lands you control.

Harmony — Warriors you control get +1/+0 and gain menace until end of turn.
Whenever Aleud Warcaller attacks, harmonize. (Trigger up to one harmony of a permanent you control.)

Menace
Whenever a creature blocks, put a -1/-1 counter on that creature at end of combat.
Creatures with -1/-1 counters on them can't block.

Menace
Whenever Algrin's Legacy becomes the target of a spell an opponent controls, that spell's controller loses 5 life unless they discard a card.

As long as you have 25 or more life, Alia's Enforcer gets +2/+2 and gains flying.
Whenever an artifact or enchantment enters the battlefield under your control, you gain 1 life.

As long as you have more life than each opponent, prevent all combat damage that would be dealt to Alia, Bearer of Morning.
[+1]: You gain 4 life.
[–2]: Exile target tapped creature. Each player draws a card.
[–8]: You get an emblem with “{W}, Pay X life: Exile target creature with power X or less.”

Lethal damage dealt to creatures is determined by their power rather than their toughness.

Whenever you cast a noncreature spell, put a quest counter on Align the Astrolabe.
At the beginning of your upkeep, create a 1/1 colorless Construct artifact creature token for each three quest counters on Align the Astrolabe.

Whenever Align with Animus Vox enters the battlefield or you attack with three or more creatures, crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)

Flying, first strike, vigilance, trample, lifelink
{4}: Put a +1/+1 counter on Alin and Meva, Warqueens.

Flying
Whenever a creature enters the battlefield under an opponent's control, you may pay {1}{B}. If you do, fateseal 1. (To fateseal 1, look at the top card of an opponent's library, then you may put it on the bottom of that player's library.)

Enchant player
At the beginning of enchanted player's upkeep, if they control two or more creatures and/or planeswalkers, they sacrifice a creature or planeswalker.

Enchant creature
Enchanted creature gets +1/+1 for each artifact and/or enchantment you control.

Vanishing 2 (This permanent enters the battlefield with two time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Whenever a time counter is removed from All Who Wander, you gain 2 life and scry 1.

When All-Blossom Memorial enters the battlefield, scry 1.
Prismatic — Whenever you cast a multicolored spell, you gain 1 life.
{T}: Add one mana of any color.

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Noncreature spells you cast cost {X} less to cast, where X is All-Encompassing Akvan's power.

[+1]: Until end of turn, All-Enduring Mafua becomes a 5/5 Cat Warrior creature with lifelink and indestructible. (He doesn't lose loyalty while he's not a planeswalker.)
[–2]: Exile target creature.
[–X]: Return each creature card with mana value X from your graveyard to your hand.

When Allagras' Vanguard enters the battlefield, create two 1/1 blue Merfolk creature tokens with “When this creature dies, draw a card, then discard a card”.

[+1]: Create a 1/1 blue Merfolk creature token with “When this creature dies, draw a card, then discard a card.”
[–1]: Target creature gets -2/-0 until your next upkeep and attacks during its controller's next turn if able.
[–7]: You get an emblem with “Creatures your opponents control get -4/-0 and attack each turn if able.”

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Alley Hunter has lifelink as long as it's blocked by a marked creature.

Alluring Rider must be blocked if able.
Attain {4}{G} ({4}{G}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)