Dual Casting

Enchant creature
Enchanted creature has "{R}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy."

Dream Devourer

Each nonland card in your hand without foretell has foretell. Its foretell cost is equal to its mana cost reduced by {2}. (During your turn, you may pay {2} and exile it from your hand face down. Cast it on a later turn for its foretell cost.)
Whenever you foretell a card, this creature gets +2/+0 until end of turn.

Shriekmaw

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When this creature enters, destroy target nonartifact, nonblack creature.
Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Wispmare

Flying
When this creature enters, destroy target enchantment.
Evoke {W} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Arcane Signet

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

Ingot Chewer

When this creature enters, destroy target artifact.
Evoke {R} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Sol Ring

Night Incarnate

Deathtouch
When this creature leaves the battlefield, all creatures get -3/-3 until end of turn.
Evoke {3}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Crackling Doom

Crackling Doom deals 2 damage to each opponent. Each opponent sacrifices a creature with the greatest power among creatures that player controls.

Excavation Technique

Demonstrate (When you cast this spell, you may copy it. If you do, choose an opponent to also copy it. Players may choose new targets for their copies.)
Destroy target nonland permanent. Its controller creates two Treasure tokens.

Wing Shards

Target player sacrifices an attacking creature of their choice.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Ruinous Ultimatum

Destroy all nonland permanents your opponents control.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Clever Lumimancer

Magecraft — Whenever you cast or copy an instant or sorcery spell, this creature gets +2/+2 until end of turn.

Haze of Rage

Buyback {2} (You may pay an additional {2} as you cast this spell. If you do, put this card into your hand as it resolves.)
Creatures you control get +1/+0 until end of turn.
Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Creative Technique

Demonstrate (When you cast this spell, you may copy it. If you do, choose an opponent to also copy it.)
Shuffle your library, then reveal cards from the top of it until you reveal a nonland card. Exile that card and put the rest on the bottom of your library in a random order. You may cast the exiled card without paying its mana cost.

Doomskar

Destroy all creatures.
Foretell {1}{W}{W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Harnfel, Horn of Bounty

Discard a card: Exile the top two cards of your library. You may play those cards this turn.

Birgi, God of Storytelling

Whenever you cast a spell, add {R}. Until end of turn, you don't lose this mana as steps and phases end.
Creatures you control can boast twice during each of your turns rather than once.

Birgi, God of Storytelling // Harnfel, Horn of Bounty

Poison the Cup

Destroy target creature. If this spell was foretold, scry 2.
Foretell {1}{B} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Dual Strike

When you next cast an instant or sorcery spell with mana value 4 or less this turn, copy that spell. You may choose new targets for the copy.
Foretell {R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Plumb the Forbidden

As an additional cost to cast this spell, you may sacrifice one or more creatures. When you do, copy this spell for each creature sacrificed this way.
You draw a card and you lose 1 life.

Double Vision

Whenever you cast your first instant or sorcery spell each turn, copy that spell. You may choose new targets for the copy.

Professor Onyx

Magecraft — Whenever you cast or copy an instant or sorcery spell, each opponent loses 2 life and you gain 2 life.
+1: You lose 1 life. Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
−3: Each opponent sacrifices a creature with the greatest power among creatures that player controls.
−8: Each opponent may discard a card. If they don't, they lose 3 life. Repeat this process six more times.

Spitebellows

When this creature leaves the battlefield, it deals 6 damage to target creature.
Evoke {1}{R}{R} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Astral Steel

Target creature gets +1/+2 until end of turn.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Fury Storm

When you cast this spell, copy it for each time you've cast your commander from the command zone this game. You may choose new targets for the copies.
Copy target instant or sorcery spell. You may choose new targets for the copy.

Stoic Farmer

When this creature enters, search your library for a basic Plains card and reveal it. If an opponent controls more lands than you, put it onto the battlefield tapped. Otherwise, put it into your hand. Then shuffle.
Foretell {1}{W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Storm-Kiln Artist

This creature gets +1/+0 for each artifact you control.
Magecraft — Whenever you cast or copy an instant or sorcery spell, create a Treasure token.

Leonin Lightscribe

Magecraft — Whenever you cast or copy an instant or sorcery spell, creatures you control get +1/+1 until end of turn.

Plains

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Awaken the Blood Avatar

As an additional cost to cast this spell, you may sacrifice any number of creatures. This spell costs {2} less to cast for each creature sacrificed this way.
Each opponent sacrifices a creature of their choice. Create a 3/6 black and red Avatar creature token with haste and "Whenever this token attacks, it deals 3 damage to each opponent."

Extus, Oriq Overlord

Double strike
Magecraft — Whenever you cast or copy an instant or sorcery spell, return target nonlegendary creature card from your graveyard to your hand.

Extus, Oriq Overlord // Awaken the Blood Avatar

Sedgemoor Witch

Menace
Ward—Pay 3 life. (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays 3 life.)
Magecraft — Whenever you cast or copy an instant or sorcery spell, create a 1/1 black and green Pest creature token with "When this token dies, you gain 1 life."