Thermo-Alchemist

Defender
{T}: Thermo-Alchemist deals 1 damage to each opponent.
Whenever you cast an instant or sorcery spell, untap Thermo-Alchemist.

Command Tower

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

Niblis of Frost

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast an instant or sorcery spell, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Electrostatic Field

Defender
Whenever you cast an instant or sorcery spell, Electrostatic Field deals 1 damage to each opponent.

Curse of the Swine

Exile X target creatures. For each creature exiled this way, its controller creates a 2/2 green Boar creature token.

Mizzix's Mastery

Exile target card that's an instant or sorcery from your graveyard. For each card exiled this way, copy it, and you may cast the copy without paying its mana cost. Exile Mizzix's Mastery.
Overload {5}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Mizzix of the Izmagnus

Whenever you cast an instant or sorcery spell with mana value greater than the number of experience counters you have, you get an experience counter.
Instant and sorcery spells you cast cost {1} less to cast for each experience counter you have.

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Sentinel Tower

Whenever an instant or sorcery spell is cast during your turn, Sentinel Tower deals damage to any target equal to 1 plus the number of instant and sorcery spells cast before that spell this turn.

Tezzeret's Gambit

({U/P} can be paid with either {U} or 2 life.)
Draw two cards, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Will Kenrith

+2: Until your next turn, up to two target creatures each have base power and toughness 0/3 and lose all abilities.
−2: Target player draws two cards. Until your next turn, instant, sorcery, and planeswalker spells that player casts cost {2} less to cast.
−8: Target player gets an emblem with "Whenever you cast an instant or sorcery spell, copy it. You may choose new targets for the copy."
Partner with Rowan Kenrith
Will Kenrith can be your commander.

Words of Wisdom

You draw two cards, then each other player draws a card.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Guttersnipe

Whenever you cast an instant or sorcery spell, this creature deals 2 damage to each opponent.

Supplant Form

Return target creature to its owner's hand. You create a token that's a copy of that creature.

Skittering Invasion

Create five 0/1 colorless Eldrazi Spawn creature tokens. They have "Sacrifice this creature: Add {C}."

Cascade Bluffs

{T}: Add {C}.
{U/R}, {T}: Add {U}{U}, {U}{R}, or {R}{R}.

Visions of Beyond

Draw a card. If a graveyard has twenty or more cards in it, draw three cards instead.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Mountain

Shivan Reef

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

Thousand-Year Storm

Whenever you cast an instant or sorcery spell, copy it for each other instant and sorcery spell you've cast before it this turn. You may choose new targets for the copies.

Island

Jace's Sanctum

Instant and sorcery spells you cast cost {1} less to cast.
Whenever you cast an instant or sorcery spell, scry 1.

Fire

Fire deals 2 damage divided as you choose among one or two targets.

Fire // Ice

Pull from Tomorrow

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Comet Storm

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.)
Choose any target, then choose another target for each time this spell was kicked. Comet Storm deals X damage to each of them.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Epic Experiment

Exile the top X cards of your library. You may cast instant and sorcery spells with mana value X or less from among them without paying their mana costs. Then put all cards exiled this way that weren't cast into your graveyard.

Arcane Signet

Banefire

Banefire deals X damage to any target.
If X is 5 or more, this spell can't be countered and the damage can't be prevented.

Final Iteration

Flying
Wizards you control get +2/+1 and have flying.
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token.

Docent of Perfection

Flying
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token. Then if you control three or more Wizards, transform Docent of Perfection.

Docent of Perfection // Final Iteration

Gigadrowse

Replicate {U} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Tap target permanent.

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Scour from Existence

Burning Prophet

Whenever you cast a noncreature spell, Burning Prophet gets +1/+0 until end of turn, then scry 1.

Murmuring Mystic

Whenever you cast an instant or sorcery spell, create a 1/1 blue Bird Illusion creature token with flying.

Will of the Naga

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Tap up to two target creatures. Those creatures don't untap during their controller's next untap step.

Price of Progress

Price of Progress deals damage to each player equal to twice the number of nonbasic lands that player controls.

Vision Skeins

Whirlpool Whelm

Clash with an opponent, then return target creature to its owner's hand. If you win, you may put that creature on top of its owner's library instead. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)

Goblin Electromancer

Instant and sorcery spells you cast cost {1} less to cast.

Snap

Return target creature to its owner's hand. Untap up to two lands.

Baral, Chief of Compliance

Instant and sorcery spells you cast cost {1} less to cast.
Whenever a spell or ability you control counters a spell, you may draw a card. If you do, discard a card.

The Mirari Conjecture

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Return target instant card from your graveyard to your hand.
II — Return target sorcery card from your graveyard to your hand.
III — Until end of turn, whenever you cast an instant or sorcery spell, copy it. You may choose new targets for the copy.

Primal Wellspring

(Transforms from Primal Amulet.)
{T}: Add one mana of any color. When that mana is spent to cast an instant or sorcery spell, copy that spell and you may choose new targets for the copy.

Primal Amulet

Instant and sorcery spells you cast cost {1} less to cast.
Whenever you cast an instant or sorcery spell, put a charge counter on Primal Amulet. Then if there are four or more charge counters on it, you may remove those counters and transform it.

Primal Amulet // Primal Wellspring

Chain Reaction

Chain Reaction deals X damage to each creature, where X is the number of creatures on the battlefield.

Jori En, Ruin Diver

Whenever you cast your second spell each turn, draw a card.

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.

Young Pyromancer

Whenever you cast an instant or sorcery spell, create a 1/1 red Elemental creature token.

Magma Jet

Magma Jet deals 2 damage to any target. Scry 2.

Firebrand Archer

Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Metallurgic Summonings

Whenever you cast an instant or sorcery spell, create an X/X colorless Construct artifact creature token, where X is that spell's mana value.
{3}{U}{U}, Exile Metallurgic Summonings: Return all instant and sorcery cards from your graveyard to your hand. Activate only if you control six or more artifacts.

Saheeli, Sublime Artificer

Whenever you cast a noncreature spell, create a 1/1 colorless Servo artifact creature token.
−2: Target artifact you control becomes a copy of another target artifact or creature you control until end of turn, except it's an artifact in addition to its other types.

Electrodominance

Electrodominance deals X damage to any target. You may cast a spell with mana value X or less from your hand without paying its mana cost.

Mind's Desire

Shuffle your library. Then exile the top card of your library. Until end of turn, you may play that card without paying its mana cost.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Act of Aggression

({R/P} can be paid with either {R} or 2 life.)
Gain control of target creature an opponent controls until end of turn. Untap that creature. It gains haste until end of turn.

Mission Briefing

Surveil 2, then choose an instant or sorcery card in your graveyard. You may cast it this turn. If that spell would be put into your graveyard, exile it instead. (To surveil 2, look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Lash Out

Lash Out deals 3 damage to target creature. Clash with an opponent. If you win, Lash Out deals 3 damage to that creature's controller. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)

Sol Ring

Walking Atlas

{T}: You may put a land card from your hand onto the battlefield.

Echoing Truth

Return target nonland permanent and all other permanents with the same name as that permanent to their owners' hands.

Ignite Memories

Target player reveals a card at random from their hand. Ignite Memories deals damage to that player equal to that card's mana value.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Sulfur Falls

Sulfur Falls enters tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.