msem-instigator

Flash
When Agent of Equilibrium enters the battlefield, destroy target creature or planeswalker an opponent controls that was dealt damage this turn.

Deception {2}{B} ({2}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Agent of Long Shadows deals combat damage to a player, you may put a Rogue card from your hand or graveyard onto the battlefield.

Whenever Agent of Vitu-Ghazi deals combat damage to a player, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Poisonous 1 (Whenever this creature deals combat damage to a player, that player gets a poison counter.)
At the beginning of your upkeep, destroy target artifact or enchantment if its controller is poisoned.

Agonizing Syphon deals 3 damage to any target and you gain 3 life.

(As this Discovery enters and after your draw step, add a progress counter. Stop after you've discovered.)
I, II — Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Discovery — {4}: You gain 2 life.

Deception {1}{B} ({1}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
When Aguri, Shadow of Doubt enters the battlefield, target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

[+2]: Create a 1/1 blue Bird creature token with flying.
[–2]: Reveal the top card of your library. If it's an enchantment or land card, put it onto the battlefield. Otherwise, put it in your hand.
[–7]: Draw seven cards.

Enchant land
When Aid from Martoob enters the battlefield, recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)
When enchanted land is tapped for mana, add one mana of any color.

Cast this spell only if creatures you control have a total power of 10 or greater or you control six or more lands.
Create two 6/6 green and white Elk creature tokens.

[+1]: Aiel Tazan deals 2 damage to any target. Then she deals 2 damage to herself unless you have her deal 2 damage to you.
[–3]: Creatures you control get +2/+0 and gain haste until end of turn.
[–X]: Create an X/1 red Elemental creature token with haste and trample. Exile that token at the beginning of the next end step. If X is 6 or more, it gains double strike.

Menace, haste
Whenever Aiel's Fury attacks, scry 2, then reveal the top card of your library. Aiel's Fury gets +X/+0 until end of turn, where X is that card's mana value.

[+1]: Exile up to one other target nonland permanent. As long as it remains exiled, its owner may pay {1} as a sorcery to put it onto the battlefield.
[–3]: Choose 0, 1, or 2. Each player sacrifices that many creatures.
[–4]: You get an emblem with “If a nonland, nontoken permanent would enter the battlefield and it wasn't cast, you may exile it instead.”

Whenever one or more counters are put on a permanent you control for the first time each turn, create that many 1/1 green Squirrel creature tokens.
{1}{G}{W}, {T}: Proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Rapport — Whenever Ainok Brushwacker and at least one other creature you control become tapped, Ainok Brushwacker gains first strike until end of turn.

Trample
When Ainok Scout enters the battlefield, nourish 2, then return a creature you control to its owner's hand. (To nourish 2, either put two +1/+1 counters on this creature or create two 1/1 white Citizen creature tokens.)

Frenzy 2 (Whenever this creature attacks and isn't blocked, it gets +2/+0 until end of turn.)
Whenever Airam, Packleader becomes blocked, other creatures you control get +1/+1 until end of turn.

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
When Aith Aera Sentinel enters the battlefield, create a 1/1 green Elf creature token.

Whenever a creature token enters the battlefield under your control, put a +1/+1 counter on target creature you control.

As long as Ajani Enlightened has an odd or even number of loyalty counters on him, he has protection from mana values of that quality.
[+1]: You gain 2 life. Untap up to two target lands.
[0]: Each player may draw a card. For each opponent that does, you draw a card.
[–3]: Create a 4/4 white Avatar creature token with “This creature can't attack if you control an Ajani planeswalker.”

[+1]: Distribute two +1/+1 counters among up to two target creatures. You gain 2 life.
[–1]: Create a 2/2 green Cat Warrior creature token.
[–3]: Exile target creature. Its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.
[–7]: You get an emblem with “Creatures you control get +X/+X, where X is your life total.”

This spell can't be countered.
Flying
Whenever Ajax, Tyrant of the Empire enters the battlefield or deals combat damage to a player, draw a card.
Whenever Ajax or another Dragon you control attacks, that Dragon deals 2 damage to any target.

You may spend mana as though it were mana of any color to cast planeswalker spells.
[–1]: Put a -1/-1 counter on target tapped creature.
[–2]: You gain 2 life for each tapped creature your opponents control.
[–3]: Destroy all creatures that attacked a planeswalker you controlled since your last turn.

Skip your draw step.
If a card would be put into your graveyard, exile it instead.
At the beginning of your upkeep, return a card from your graveyard to your hand. If you can't, you draw a card and you lose 1 life.

Trample
Wanderlust — Whenever Akkrixian Assailants attacks, if you control four or more differently named lands, put a +1/+1 counter on it.