Arcane Signet

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

Counterspell

Harmonic Prodigy

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
If an ability of a Shaman or another Wizard you control triggers, that ability triggers an additional time.

The Great Work

(As this Saga enters and after your draw step, add a lore counter.)
I — The Great Work deals 3 damage to target opponent and each creature they control.
II — Create three Treasure tokens.
III — Until end of turn, you may cast instant and sorcery spells from any graveyard. If a spell cast this way would be put into a graveyard, exile it instead. Exile The Great Work, then return it to the battlefield (front face up).

Urabrask

First strike
Whenever you cast an instant or sorcery spell, Urabrask deals 1 damage to target opponent. Add {R}.
{R}: Exile Urabrask, then return it to the battlefield transformed under its owner's control. Activate only as a sorcery and only if you've cast three or more instant and/or sorcery spells this turn.

Urabrask // The Great Work

Quintorius, Loremaster

Vigilance
At the beginning of your end step, exile target noncreature, nonland card from your graveyard. Create a 3/2 red and white Spirit creature token.
{1}{R}{W}, {T}, Sacrifice a Spirit: Choose target card exiled with Quintorius. You may cast that card this turn without paying its mana cost. If that spell would be put into a graveyard, put it on the bottom of its owner's library instead.

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Mystic Monastery

Mystic Monastery enters tapped.
{T}: Add {U}, {R}, or {W}.

Seachrome Coast

Seachrome Coast enters tapped unless you control two or fewer other lands.
{T}: Add {W} or {U}.

Kykar, Wind's Fury

Flying
Whenever you cast a noncreature spell, create a 1/1 white Spirit creature token with flying.
Sacrifice a Spirit: Add {R}.