Toxic Deluge

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

Psychic Corrosion

Whenever you draw a card, each opponent mills two cards.

Brainstorm

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

Notion Thief

Flash
If an opponent would draw a card except the first one they draw in each of their draw steps, instead that player skips that draw and you draw a card.

Evil Twin

You may have Evil Twin enter as a copy of any creature on the battlefield, except it has "{U}{B}, {T}: Destroy target creature with the same name as this creature."

Talisman of Dominance

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

Pact of Negation

Counter target spell.
At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Dimir Signet

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.)

Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters tapped unless you control two or more basic lands.

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.

Swamp

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.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Animate Dead

Enchant creature card in a graveyard
When Animate Dead enters, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Animate Dead." Return enchanted creature card to the battlefield under your control and attach Animate Dead to it. When Animate Dead leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets -1/-0.

Phyrexian Metamorph

({U/P} can be paid with either {U} or 2 life.)
You may have Phyrexian Metamorph enter as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Psychic Strike

Counter target spell. Its controller mills two cards.

Shipwreck Marsh

Shipwreck Marsh enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Urborg Scavengers

Whenever Urborg Scavengers enters or attacks, exile target card from a graveyard. Put a +1/+1 counter on Urborg Scavengers.
Urborg Scavengers has flying as long as a card exiled with it has flying. The same is true for first strike, double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, reach, trample, and vigilance.

Traumatize

Target player mills half their library, rounded down.

Nephalia Drownyard

{T}: Add {C}.
{1}{U}{B}, {T}: Target player mills three cards.

Commander's Sphere

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

Clever Impersonator

You may have Clever Impersonator enter as a copy of any nonland permanent on the battlefield.

Memory Erosion

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

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.

Murkwater Pathway

Clearwater Pathway

Clearwater Pathway // Murkwater Pathway

Watery Grave

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

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

Dimir Aqueduct

Dimir Aqueduct enters tapped.
When Dimir Aqueduct enters, return a land you control to its owner's hand.
{T}: Add {U}{B}.

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.

Bloodchief Ascension

At the beginning of each end step, if an opponent lost 2 or more life this turn, you may put a quest counter on Bloodchief Ascension. (Damage causes loss of life.)
Whenever a card is put into an opponent's graveyard from anywhere, if Bloodchief Ascension has three or more quest counters on it, you may have that player lose 2 life. If you do, you gain 2 life.

Windfall

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

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

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.")

Extract from Darkness

Each player mills two cards. Then you put a creature card from a graveyard onto the battlefield under your control.

Lazav, Dimir Mastermind

Hexproof
Whenever a creature card is put into an opponent's graveyard from anywhere, you may have Lazav, Dimir Mastermind become a copy of that card, except its name is Lazav, Dimir Mastermind, it's legendary in addition to its other types, and it has hexproof and this ability.

Thought Collapse

Counter target spell. Its controller mills three cards.

Sol Ring

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Sepulchral Primordial

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
When Sepulchral Primordial enters, for each opponent, you may put up to one target creature card from that player's graveyard onto the battlefield under your control.

Dimir Doppelganger

{1}{U}{B}: Exile target creature card from a graveyard. Dimir Doppelganger becomes a copy of that card, except it has this ability.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

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.

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. Underground River deals 1 damage to you.

Court of Cunning

When Court of Cunning enters, you become the monarch.
At the beginning of your upkeep, any number of target players each mill two cards. If you're the monarch, each of those players mills ten cards instead. (To mill a card, a player puts the top card of their library into their graveyard.)

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.

Body Double

You may have Body Double enter as a copy of any creature card in a graveyard.

One Ring to Rule Them All

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — The Ring tempts you, then each player mills cards equal to your Ring-bearer's power.
II — Destroy all nonlegendary creatures.
III — Each opponent loses 1 life for each creature card in that player's graveyard.

Bojuka Bog

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

Command Tower

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

Scheming Symmetry

Choose two target players. Each of them searches their library for a card, then shuffles and puts that card on top.

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.

Whispering Madness

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.
Cipher (Then you may exile this spell card encoded on a creature you control. Whenever that creature deals combat damage to a player, its controller may cast a copy of the encoded card without paying its mana cost.)

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.

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.

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.)

Arcane Signet

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {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.

Terisian Mindbreaker

Whenever Terisian Mindbreaker attacks, defending player mills half their library, rounded up.
Unearth {1}{U}{U}{U} ({1}{U}{U}{U}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Tainted Isle

{T}: Add {C}.
{T}: Add {U} or {B}. Activate only if you control a Swamp.

Shadow Kin

Flash
At the beginning of your upkeep, each player mills three cards. You may exile a creature card from among the cards milled this way. If you do, Shadow Kin becomes a copy of that card, except it has this ability.

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.

Sunken Ruins

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

Can't Wake Up

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

Cruel Somnophage

Cruel Somnophage's power and toughness are each equal to the number of creature cards in all graveyards.

Cruel Somnophage // Can't Wake Up

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad, the Grim deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Damnation

Destroy all creatures. They can't be regenerated.

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.

Memory Plunder

You may cast target instant or sorcery card from an opponent's graveyard without paying its mana cost.

Infernal Grasp

Destroy target creature. You lose 2 life.

Thief of Sanity

Flying
Whenever Thief of Sanity deals combat damage to a player, look at the top three cards of that player's library, exile one of them face down, then put the rest into their graveyard. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Feed the Swarm

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

Sword of Body and Mind

Equipped creature gets +2/+2 and has protection from green and from blue.
Whenever equipped creature deals combat damage to a player, you create a 2/2 green Wolf creature token and that player mills ten cards.
Equip {2}

Visions of Beyond

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

Reliquary Tower

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

Island

Realmbreaker, the Invasion Tree

{2}, {T}: Target opponent mills three cards. Put a land card from their graveyard onto the battlefield tapped under your control. It gains "If this land would leave the battlefield, exile it instead of putting it anywhere else."
{10}, {T}, Sacrifice Realmbreaker, the Invasion Tree: Search your library for any number of Praetor cards, put them onto the battlefield, then shuffle.

Didn't Say Please

Morphic Pool

Morphic Pool enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Phenax, God of Deception

Indestructible
As long as your devotion to blue and black is less than seven, Phenax isn't a creature.
Creatures you control have "{T}: Target player mills X cards, where X is this creature's toughness."

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Mesmeric Orb

Whenever a permanent becomes untapped, that permanent's controller mills a card.

Jace, the Perfected Mind

Compleated ({U/P} can be paid with {U} or 2 life. If life was paid, this planeswalker enters with two fewer loyalty counters.)
+1: Until your next turn, up to one target creature gets -3/-0.
−2: Target player mills three cards. Then if a graveyard has twenty or more cards in it, you draw three cards. Otherwise, you draw a card.
−X: Target player mills three times X cards.

Counterspell

Mindcrank

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

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.