msem-instigator

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Scry 2.
II — Draw two cards.
III — Spells you cast this turn cost {2} less to cast.

When Ageless Ascetic enters the battlefield, return up to one target instant or sorcery card from your graveyard to your hand.

Flying
When Ageless Lorekeeper enters the battlefield, you may discard your hand. When you do, draw three cards.

Whenever a land enters the battlefield under your control, untap Ageless Wanderer.
{1}, {T}: Add one mana of any color.

When Ageless Weaver enters the battlefield, create a green Aura enchantment token named Years of Experience attached to target creature. The token has enchant creature and “Enchanted creature gets +2/+2.”
Whenever an enchanted creature you control dies, create a 3/3 green Elemental creature token.

Whenever a creature you control dies, put a +1/+1 counter on Agent of Andazir.

Flash
When Agent of Deception enters the battlefield, counter target creature or planeswalker spell unless its controller pays {X}, where X is your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

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.”)

Target creature you control deals damage equal to its power to target creature you don't control.

Menace, trample, indestructible
Whenever Aghavaan Unleashed deals combat damage to a player, that player gets that many poison counters.
At the beginning of your end step, sacrifice another creature or transform Aghavaan Unleashed.

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.

{T}: Add {C}.
At the beginning of each end step, if you control five or more Snake creatures, transform Aghavaan's Wound.

As an additional cost to cast this spell, sacrifice a creature.
Torment target player three times. (They lose 3 life unless they discard a card or sacrifice a nonland permanent.)

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

At the beginning of your precombat main phase, exile target card in a graveyard. If it's a creature card, put a +1/+1 counter on target creature you control. If it's a land card, add {C}. If it's a noncreature, nonland card, 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.

{T}, Discard a card: Add {C}.
Whenever you discard one or more cards, you may pay {2}. If you do, draw a card.

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.