msem-instigator

Arcane Oasis enters tapped unless you control another Desert.
{T}: Add {U} or {R}.

Arcane Sanctum enters tapped.
{T}: Add {W}, {U}, or {B}.

Harmony — Attach Arcane Saxophone to target creature.
When Arcane Saxophone enters, 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.

Whenever you cast a spell, draw a card if that spell has the same name as a card in your graveyard.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

If you casting a noncreature spell causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
Cycling {2} ({2}, Discard this card: Draw a card.)

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

When Arcanomancer enters, return up to one target instant card and up to one target sorcery card from your graveyard to your hand.

Flying
When Arcanum Owl enters, you may return target instant or sorcery card from your graveyard to your hand.

Lifelink
Arcblade Enforcers gets +1/+1 as long as you control an enchantment.

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

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.)

Flying
Concord — When Archangel of Accord enters, if there are four or more card types among permanents you control, destroy all other creatures.

Flying
You may cast enchantment spells from your graveyard.
Whenever an enchantment you control enters, draw a card.

Flying, lifelink
When Archdemon Shilgengar enters, exile all land cards from your graveyard, exchange your graveyard and library, then shuffle your library.
You can only cast spells by paying life equal to their mana value rather than paying their mana cost.

Flying, trample
Once each turn, when you cast a spell from anywhere other than your hand, you may copy it. If you do, you may choose new targets for the copy.

Whenever you cast a noncreature spell, Architect of Calamity deals 2 damage to each opponent.

When Architect of the Derezzed enters, create two 1/1 colorless Servo artifact creature tokens.
Sacrifice an artifact: Target creature can't be blocked this turn.

When Archive Guardian enters, return target card from your graveyard to your hand.
Recite {1}{B}{G} (You may cast this creature from your graveyard for its recite cost. If you do, exile it when it enters or if it would leave the battlefield.)

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

When Archivist Heretic enters, you lose 1 life, then investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Flying, prowess

Whenever Archlegislator attacks, adjudicate. (Create a white Aura enchantment token with enchant creature and “Sacrifice this token: Untap enchanted creature” attached to target creature.)
{3}{R}{R}, {T}, Sacrifice an Aura: Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.

You have no maximum hand size.
{T}: Add {C}.
{1}, {T}: Add one mana of any color.