Spellskite

{U/P}: Change a target of target spell or ability to Spellskite. ({U/P} can be paid with either {U} or 2 life.)

Psychic Strike

Counter target spell. Its controller mills two cards.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Zellix, Sanity Flayer

Hive Mind — Whenever a player mills one or more creature cards, you create a 1/1 black Horror creature token.
{1}, {T}: Target player mills three cards.
Choose a Background (You can have a Background as a second commander.)

Undercity Sewers

({T}: Add {U} or {B}.)
Undercity Sewers enters tapped.
When Undercity Sewers enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Hedron Crab

Landfall — Whenever a land you control enters, target player mills three cards.

Maddening Cacophony

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

Infernal Grasp

Destroy target creature. You lose 2 life.

Glimpse the Unthinkable

Snapcaster Mage

Flash
When Snapcaster Mage enters, target instant or sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost. (You may cast that card from your graveyard for its flashback cost. Then exile it.)

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.

Ponder

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

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.)

Island

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Kami of the Crescent Moon

At the beginning of each player's draw step, that player draws an additional card.

Restless Reef

Restless Reef enters tapped.
{T}: Add {U} or {B}.
{2}{U}{B}: Until end of turn, Restless Reef becomes a 4/4 blue and black Shark creature with deathtouch. It's still a land.
Whenever Restless Reef attacks, target player mills four cards.

Ashiok, Dream Render

Spells and abilities your opponents control can't cause their controller to search their library.
−1: Target player mills four cards. Then exile each opponent's graveyard.

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.)

Traumatize

Target player mills half their library, rounded down.

Sewer Nemesis

As Sewer Nemesis enters, choose a player.
Sewer Nemesis's power and toughness are each equal to the number of cards in the chosen player's graveyard.
Whenever the chosen player casts a spell, that player mills a card.

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

Grisly Spectacle

Destroy target nonartifact creature. Its controller mills cards equal to that creature's power.

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.

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Windfall

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

Jace's Archivist

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

Negate

Riddlekeeper

Whenever a creature attacks you or a planeswalker you control, that creature's controller mills two cards.

Watery Grave

({T}: Add {U} or {B}.)
As Watery Grave enters, you may pay 2 life. If you don't, it enters tapped.

Thought Scour

Target player mills two cards.
Draw a card.

Archive Trap

If an opponent searched their library this turn, you may pay {0} rather than pay this spell's mana cost.
Target opponent mills thirteen cards.

Tasha's Hideous Laughter

Each opponent exiles cards from the top of their library until that player has exiled cards with total mana value 20 or more.

Counterspell

Overwhelmed Apprentice

When Overwhelmed Apprentice enters, each opponent mills two cards. Then you scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Dread Summons

Each player mills X cards. For each creature card put into a graveyard this way, you create a tapped 2/2 black Zombie creature token. (To mill a card, a player puts the top card of their library into their graveyard.)

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

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.

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.

Swamp

Nemesis of Reason

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

Murkwater Pathway

Clearwater Pathway

Clearwater Pathway // Murkwater Pathway

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.)

Drown in Dreams

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Target player draws X cards.
• Target player mills twice X cards.