Imposing Grandeur

Each player may discard their hand and draw cards equal to the greatest mana value of a commander they own on the battlefield or in the command zone.

Zariel, Archduke of Avernus

+1: Creatures you control get +1/+0 and gain haste until end of turn.
0: Create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."
−6: You get an emblem with "At the end of the first combat phase on your turn, untap target creature you control. After this phase, there is an additional combat phase."

Chandra's Ignition

Target creature you control deals damage equal to its power to each other creature and each opponent.

Swamp

Duskmantle Guildmage

{1}{U}{B}: Whenever a card is put into an opponent's graveyard from anywhere this turn, that player loses 1 life.
{2}{U}{B}: Target player mills two cards.

Feldon of the Third Path

{2}{R}, {T}: Create a token that's a copy of target creature card in your graveyard, except it's an artifact in addition to its other types. It gains haste. Sacrifice it at the beginning of the next end step.

Dragon Breath

Enchant creature
Enchanted creature has haste.
{R}: Enchanted creature gets +1/+0 until end of turn.
When a creature with mana value 6 or greater enters, you may return Dragon Breath from your graveyard to the battlefield attached to that creature.

The Haunt of Hightower

Flying, lifelink
Whenever The Haunt of Hightower attacks, defending player discards a card.
Whenever a card is put into an opponent's graveyard from anywhere, put a +1/+1 counter on The Haunt of Hightower.

Traumatize

Target player mills half their library, rounded down.

Siren of the Silent Song

Flying
Inspired — Whenever Siren of the Silent Song becomes untapped, each opponent discards a card, then each opponent mills a card.

Strionic Resonator

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

Keening Stone

{5}, {T}: Target player mills X cards, where X is the number of cards in that player's graveyard.

Nemesis of Reason

Whenever Nemesis of Reason attacks, defending player mills ten cards.

Chainer, Nightmare Adept

Discard a card: You may cast a creature spell from your graveyard this turn. Activate only once each turn.
Whenever a nontoken creature you control enters, if you didn't cast it from your hand, it gains haste until your next turn.

Mountain

Guiltfeeder

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Whenever Guiltfeeder attacks and isn't blocked, defending player loses 1 life for each card in their graveyard.

Lord Xander, the Collector

When Lord Xander, the Collector enters, target opponent discards half the cards in their hand, rounded down.
Whenever Lord Xander attacks, defending player mills half their library, rounded down.
When Lord Xander dies, target opponent sacrifices half the nonland permanents they control of their choice, rounded down.

Dreamborn Muse

At the beginning of each player's upkeep, that player mills X cards, where X is the number of cards in their hand.

Anger

Haste
As long as Anger is in your graveyard and you control a Mountain, creatures you control have haste.

Induce Paranoia

Counter target spell. If {B} was spent to cast this spell, that spell's controller mills X cards, where X is the spell's mana value.

Arcane Signet

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

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.

Tuktuk Rubblefort

Defender, reach
Creatures you control have haste.

Maestros Theater

When Maestros Theater enters, sacrifice it. When you do, search your library for a basic Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Charcoal Diamond

Charcoal Diamond enters tapped.
{T}: Add {B}.

Maddening Cacophony

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

Sky Diamond

Mirko Vosk, Mind Drinker

Flying
Whenever Mirko Vosk, Mind Drinker deals combat damage to a player, that player reveals cards from the top of their library until they reveal four land cards, then puts those cards into their graveyard.

Memory Erosion

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

Bruvac the Grandiloquent

If an opponent would mill one or more cards, they mill twice that many cards instead. (To mill a card, a player puts the top card of their library into their graveyard.)

Mind Funeral

Target opponent reveals cards from the top of their library until four land cards are revealed. That player puts all cards revealed this way into their graveyard.

Lightning Runner

Double strike, haste
Whenever Lightning Runner attacks, you get {E}{E} (two energy counters), then you may pay eight {E}. If you pay, untap all creatures you control, and after this phase, there is an additional combat phase.

Drown in the Loch

Choose one —
• Counter target spell with mana value less than or equal to the number of cards in its controller's graveyard.
• Destroy target creature with mana value less than or equal to the number of cards in its controller's graveyard.

Mind Grind

Each opponent reveals cards from the top of their library until they reveal X land cards, then puts all cards revealed this way into their graveyard. X can't be 0.

Island

Persistent Nightmare

Skulk (This creature can't be blocked by creatures with greater power.)
When Persistent Nightmare deals combat damage to a player, return it to its owner's hand.

Startled Awake

Target opponent mills thirteen cards.
{3}{U}{U}: Put Startled Awake from your graveyard onto the battlefield transformed. Activate only as a sorcery.

Startled Awake // Persistent Nightmare

Last One Standing

Choose a creature at random, then destroy the rest.

Bond of Insight

Each player mills four cards. Return up to two instant and/or sorcery cards from your graveyard to your hand. Exile Bond of Insight.

Imperious Mindbreaker

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Imperious Mindbreaker is paired with another creature, each of those creatures has "Whenever this creature attacks, each opponent mills cards equal to its toughness."

Mindcrank

Whenever an opponent loses life, that player mills that many cards. (Damage causes loss of life.)

Bloodsworn Steward

Flying
Commander creatures you control get +2/+2 and have haste.

Nighthowler

Bestow {2}{B}{B} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Nighthowler and enchanted creature each get +X/+X, where X is the number of creature cards in all graveyards.

Port Razer

Whenever Port Razer deals combat damage to a player, untap each creature you control. After this phase, there is an additional combat phase.
Port Razer can't attack a player it has already attacked this turn.

Cursed Mirror

{T}: Add {R}.
As Cursed Mirror enters, you may have it become a copy of any creature on the battlefield until end of turn, except it has haste.

Cut Your Losses

Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Target player mills half their library, rounded down.

Manic Scribe

When Manic Scribe enters, each opponent mills three cards.
Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, that player mills three cards.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Command Tower

Fervor

Creatures you control have haste. (They can attack and {T} as soon as they come under your control.)

Nightscape Familiar

Blue spells and red spells you cast cost {1} less to cast.
{1}{B}: Regenerate Nightscape Familiar.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Wight of Precinct Six

Wight of Precinct Six gets +1/+1 for each creature card in your opponents' graveyards.

Entering

Put a creature card from a graveyard onto the battlefield under your control. It gains haste until end of turn.
Fuse (You may cast one or both halves of this card from your hand.)

Breaking

Target player mills eight cards.
Fuse (You may cast one or both halves of this card from your hand.)

Breaking // Entering

Sinister Waltz

Choose three target creature cards in your graveyard. Return two of them at random to the battlefield and put the other on the bottom of your library.

Consuming Aberration

Consuming Aberration's power and toughness are each equal to the number of cards in your opponents' graveyards.
Whenever you cast a spell, each opponent reveals cards from the top of their library until they reveal a land card, then puts those cards into their graveyard.

Dimir Signet

Crumbling Necropolis

Crumbling Necropolis enters tapped.
{T}: Add {U}, {B}, or {R}.

Rakdos Signet

Commander's Sphere

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

Thought Vessel

Folio of Fancies

Players have no maximum hand size.
{X}{X}, {T}: Each player draws X cards.
{2}{U}, {T}: Each opponent mills cards equal to the number of cards in their hand.

Kaya's Ghostform

Enchant creature or planeswalker you control
When enchanted permanent dies or is put into exile, return that card to the battlefield under your control.

Pilfered Plans

Target player mills two cards. Draw two cards.

Xander's Lounge

({T}: Add {U}, {B}, or {R}.)
Xander's Lounge enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Sol Ring

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.

Mortivore

Mortivore's power and toughness are each equal to the number of creature cards in all graveyards.
{B}: Regenerate Mortivore. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Szadek, Lord of Secrets

Flying
If Szadek, Lord of Secrets would deal combat damage to a player, instead put that many +1/+1 counters on Szadek and that player mills that many cards.

Fleet Swallower

Whenever Fleet Swallower attacks, target player mills half their library, rounded up.

Relentless Assault

Untap all creatures that attacked this turn. After this main phase, there is an additional combat phase followed by an additional main phase.

Flamekin Village

As Flamekin Village enters, you may reveal an Elemental card from your hand. If you don't, Flamekin Village enters tapped.
{T}: Add {R}.
{R}, {T}: Target creature gains haste until end of turn.