Maelstrom Muse

Flying
Whenever this creature attacks, the next instant or sorcery spell you cast this turn costs {X} less to cast, where X is this creature's power as this ability resolves.

Harmonic Prodigy

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

Seize the Day

Untap target creature. After this main phase, there is an additional combat phase followed by an additional main phase.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Muddle, the Ever-Changing

Whenever you cast an instant or sorcery spell, Muddle becomes a copy of up to one target nonlegendary creature you control until end of turn, except it has myriad. (Whenever it attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Najal, the Storm Runner

You may cast sorcery spells as though they had flash.
Whenever Najal attacks, you may pay {2}. If you do, when you next cast an instant or sorcery spell this turn, copy it. You may choose new targets for the copy.

Wizards of Thay

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Instant and sorcery spells you cast cost {1} less to cast.
You may cast sorcery spells as though they had flash.

Fury of the Horde

You may exile two red cards from your hand rather than pay this spell's mana cost.
Untap all creatures that attacked this turn. After this main phase, there is an additional combat phase followed by an additional main phase.

The Dawning Archaic

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Reach
Whenever The Dawning Archaic attacks, you may cast target instant or sorcery card from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.