Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Traumatize

Target player mills half their library, rounded down.

Memory Erosion

Whenever an opponent casts a spell, that player mills two cards.

Miscast

Counter target instant or sorcery spell unless its controller pays {3}.

Madblind Mountain

({T}: Add {R}.)
Madblind Mountain enters tapped.
{R}, {T}: Shuffle your library. Activate only if you control two or more red permanents.

Island

Kessig Flamebreather

Whenever you cast a noncreature spell, Kessig Flamebreather deals 1 damage to each opponent.

Brimstone Volley

Brimstone Volley deals 3 damage to any target.
Morbid — Brimstone Volley deals 5 damage instead if a creature died this turn.

Decanter of Endless Water

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

Aetherize

Return all attacking creatures to their owner's hand.

Shock

Guttersnipe

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

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Thought Collapse

Counter target spell. Its controller mills three cards.

Wall of Lost Thoughts

Defender (This creature can't attack.)
When Wall of Lost Thoughts enters, target player mills four cards. (They put the top four cards of their library into their graveyard.)

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Maddening Cacophony

Kicker {3}{U}
Each opponent mills eight cards. If this spell was kicked, instead each opponent mills half their library, rounded up.

Stormcarved Coast

Stormcarved Coast enters tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

Fractured Sanity

Each opponent mills fourteen cards.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)
When you cycle Fractured Sanity, each opponent mills four cards.

Pillar of Flame

Pillar of Flame deals 2 damage to any target. If a creature dealt damage this way would die this turn, exile it instead.

Ruin Crab

Landfall — Whenever a land you control enters, each opponent mills three cards. (To mill a card, a player puts the top card of their library into their graveyard.)

Counterspell

Tome Scour

Mind Sculpt

Mountain

Sulfur Falls

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

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.)

Arcane Signet

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

Drowned Secrets

Whenever you cast a blue spell, target player mills two cards.

Fanatical Firebrand

Haste (This creature can attack and {T} as soon as it comes under your control.)
{T}, Sacrifice this creature: It deals 1 damage to any target.

Command Tower

Cursecatcher

Sacrifice Cursecatcher: Counter target instant or sorcery spell unless its controller pays {1}.

Flames of the Blood Hand

Flames of the Blood Hand deals 4 damage to target player or planeswalker. The damage can't be prevented. If that player or that planeswalker's controller would gain life this turn, that player gains no life instead.

Cascade Bluffs

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

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Reverberate

Copy target instant or sorcery spell. You may choose new targets for the copy.

Psychic Spiral

Shuffle all cards from your graveyard into your library. Target player mills that many cards.

Skullcrack

Players can't gain life this turn. Damage can't be prevented this turn. Skullcrack deals 3 damage to target player or planeswalker.

Venture Deeper

Target player mills four cards. (Then exile this card. You may cast the creature later from exile.)

Merfolk Secretkeeper

Merfolk Secretkeeper // Venture Deeper

Will, Scholar of Frost

Instant and sorcery spells you cast cost {1} less to cast.
+1: Up to one target creature has base power and toughness 0/2 until your next turn.
−3: Draw two cards.
−7: Exile up to five target permanents. For each permanent exiled this way, its controller creates a 4/4 blue and red Elemental creature token.

Rowan, Scholar of Sparks

Instant and sorcery spells you cast cost {1} less to cast.
+1: Rowan, Scholar of Sparks deals 1 damage to each opponent. If you've drawn three or more cards this turn, she deals 3 damage to each opponent instead.
−4: You get an emblem with "Whenever you cast an instant or sorcery spell, you may pay {2}. If you do, copy that spell. You may choose new targets for the copy."

Rowan, Scholar of Sparks // Will, Scholar of Frost

Sphinx's Tutelage

Whenever you draw a card, target opponent mills two cards. If two nonland cards that share a color were milled this way, repeat this process.
{5}{U}: Draw a card, then discard a card.

Thought Scour

Target player mills two cards.
Draw a card.

Timetwister

Each player shuffles their hand and graveyard into their library, then draws seven cards. (Then put Timetwister into its owner's graveyard.)