msem-instigator

Equipped creature gets +2/+2.
Whenever equipped creature deals combat damage to a player, exile cards from the top of their library until they exile a nonland card. You may cast that card without paying its mana cost.
Equip {2}

As long as Arboreal Runes is on the battlefield or in your graveyard, it's a Forest land in addition to its other types.
{T}: Add one mana of any color.

Activated abilities of artifacts cost {2} more to activate.

Harmony — Attach Arcane Saxophone to target creature.
When Arcane Saxophone enters the battlefield, harmonize. (Trigger up to one harmony of one permanent you control.)
Equipped creature gets +2/+2.
Equip {4}

{T}: Add one mana of any color in your commander's color identity.

Equipped creature gets +1/+0.
Whenever equipped creature attacks, you may draw a card then discard a card.
Equip {2}

This spell costs {1} less to cast for each enchantment you control.
Flying, lifelink, trample
Disturb {6}{B}{B}. That spell costs {1} less to cast for each enchantment you control. (You may cast this card from your graveyard transformed for its disturb cost.)

Reach
When Archived Intelligence enters the battlefield, surveil 2. Then if you control a token, draw a card.

{T}: Add {C}.
{2}, {T}, Sacrifice Arcor Diamond: Draw a card.

You may choose not to untap Arden, Mirrormage during your untap step.
Whenever Arden becomes untapped or leaves the battlefield, sacrifice all tokens created with it.
{3}{U}, {T}: Create a token that's a copy of another creature on the battlefield.

[+1]: Search your library for a land card, put it onto the battlefield, untap it, then shuffle. Sacrifice a land.
[–2]: Destroy target noncreature permanent. Its controller may search their library for a basic land card, put that card onto the battlefield, then shuffle.
[–6]: Return any number of land cards from your graveyard to the battlefield and untap them. They become 3/3 creatures with haste in addition to their other types.

[+1]: Untap target land.
[–1]: Exile the top card of your library. You may play that card until end of turn. If a land card is exiled this way, you gain 2 life.
[–7]: Untap each land you control. Lands you control become 3/3 Elemental creatures with haste until end of turn. They're still lands.

[+1]: Tap up to one target creature. It doesn't untap during its controller's next untap step.
[–2]: Exile target card from a graveyard. Create a 2/2 blue and black Elemental creature token.
[–7]: You get an emblem with “You may play cards from exile.”

{U}{B}, {T}: Draw a card, then each player exiles the top card of their library. Then if a player owns two or more cards exiled with Arina, Volarian Explorer, exile her, then return her to the battlefield transformed under her owner's control.

Menace, haste
As long as Arleigh, Spellblade Prodigy is tapped, the first spell you cast during each other player's turn costs {U/R} less to cast. This effect reduces only the amount of colored mana you pay. (For example, if you cast a spell with mana cost {1}{R}, it costs {1} to cast.)

At the beginning of your end step, you may put a progress counter on Armored Transports.
[PROGRESS 1-2] Creatures you control get +0/+1.
[PROGRESS 3+] Creatures you control get +0/+1 and have vigilance.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Exile each player's graveyard. Create a token that's a copy of a creature card exiled this way.
III — Create a token that's a copy of an artifact or enchantment card exiled with Around the Plane in Three Days.
Create a token that's a copy of a land or planeswalker card exiled with Around the Plane in Three Days.

When Arpechian Groundskeeper enters the battlefield, rouse 1. (Put a +1/+1 counter on a permanent you control. If it isn't a creature, tap it and it becomes a 0/0 creature in addition to its other types.)
Remove a +1/+1 counter from Arpechian Groundskeeper: Draw a card.

Once during each of your turns, when a card is put into a graveyard from anywhere, you may cast it. You may spend mana of any color to cast that spell.
When Arroyo, Infinitely Branching is put into your graveyard from anywhere, you may cast it.

If a player would draw a card, instead that player may put a card they own exiled with Arroyo, the Bound into their hand.
{3}: Search target player's library for a card and exile it face down, then that player shuffles. They may look at that card for as long as it remains exiled.

{1}{G/W}: Put a +1/+1 counter on Artful Chari.
Whenever you cast an instant or sorcery spell, you may remove a number of +1/+1 counters from Chari equal to that spell's mana value. If you do, copy that spell, and you may choose new targets for the copy.

Flying
At the beginning of your upkeep, you may create a token that is a copy of target Aura you control and attach it to target permanent or player it could enchant.
{2}, Sacrifice an Aura: Artiaburz gains indestructible and hexproof until end of turn.

When Artian, Phyrexian Architect enters the battlefield, search your library for a land card, put it onto the battlefield, then shuffle.
At the beginning of your upkeep, put a corruption counter on a land you control. Then create a 1/1 colorless Phyrexian artifact creature token for each land you control with a corruption counter on it.

Flying
Improve {1}{U} ({1}{U}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)

At the beginning of each upkeep, if an opponent controls more creatures than you, create a 1/1 colorless Thopter artifact creature token with flying.