Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

Serrated Scorpion

When this creature dies, it deals 2 damage to each opponent and you gain 2 life.

Stonespeaker Crystal

{T}: Add {C}{C}.
{2}, {T}, Sacrifice this artifact: Exile any number of target players' graveyards. Draw a card.

Swamp

Extract from Darkness

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

Dark Hatchling

Flying
When this creature enters, destroy target nonblack creature. It can't be regenerated.

Blood Money

Destroy all creatures. For each nontoken creature destroyed this way, you create a tapped Treasure token.

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.)

Sigil of Myrkul

At the beginning of combat on your turn, mill a card. When you do, if there are four or more creature cards in your graveyard, put a +1/+1 counter on target creature you control and it gains deathtouch until end of turn. (To mill a card, put the top card of your library into your graveyard.)

The Myriad Pools

(Transforms from The Everflowing Well.)
{T}: Add {U}.
Whenever you cast a permanent spell using mana produced by The Myriad Pools, up to one other target permanent you control becomes a copy of that spell until end of turn.

The Everflowing Well

When The Everflowing Well enters, mill two cards, then draw two cards.
Descend 8 — At the beginning of your upkeep, if there are eight or more permanent cards in your graveyard, transform The Everflowing Well.

The Everflowing Well // The Myriad Pools

Fatal Push

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent left the battlefield under your control this turn.

Command Tower

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

Temple of Deceit

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {U} or {B}.

Dimir Keyrune

{T}: Add {U} or {B}.
{U}{B}: This artifact becomes a 2/2 blue and black Horror artifact creature until end of turn and can't be blocked this turn.

Butcher of Malakir

Flying
Whenever this creature or another creature you control dies, each opponent sacrifices a creature of their choice.

Rogue's Passage

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

Dimir Signet

Conduit Pylons

When this land enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Araumi of the Dead Tide

{T}, Exile cards from your graveyard equal to the number of opponents you have: Target creature card in your graveyard gains encore until end of turn. The encore cost is equal to its mana cost. (Exile the creature card and pay its mana cost: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Elder Brain

Menace
Whenever this creature attacks a player, exile all cards from that player's hand, then they draw that many cards. You may play lands and cast spells from among the exiled cards for as long as they remain exiled. If you cast a spell this way, you may spend mana as though it were mana of any color to cast it.

Towering-Wave Mystic

Whenever this creature deals damage, target player mills that many cards.

Command the Dreadhorde

Choose any number of target creature and/or planeswalker cards in graveyards. Command the Dreadhorde deals damage to you equal to the total mana value of those cards. Put them onto the battlefield under your control.

Guildsworn Prowler

Deathtouch
When this creature dies, if it wasn't blocking, draw a card.

Mulldrifter

Flying
When this creature enters, draw two cards.
Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Tormod, the Desecrator

Whenever one or more cards leave your graveyard, create a tapped 2/2 black Zombie creature token.
Partner (You can have two commanders if both have partner.)

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Dimir Aqueduct

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

Ruthless Deathfang

Flying
Whenever you sacrifice a creature, target opponent sacrifices a creature of their choice.

Dazzling Lights

Target creature gets -3/-0 until end of turn.
Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Uchuulon

Uchuulon's power is equal to the number of Crabs, Oozes, and/or Horrors you control.
Horrific Symbiosis — At the beginning of your end step, exile up to one target creature card from an opponent's graveyard. If you do, create a token that's a copy of this creature.

Tocasia's Dig Site

{T}: Add {C}.
{3}, {T}: Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Nephalia Drownyard

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

Drag the Canal

Create a 2/2 white and blue Detective creature token. If a creature died this turn, you gain 2 life, surveil 2, then investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Liliana's Scorn

Destroy target creature. You may search your library and/or graveyard for a card named Liliana, Death Mage, reveal it, and put it into your hand. If you search your library this way, shuffle.

Plague Spitter

At the beginning of your upkeep, this creature deals 1 damage to each creature and each player.
When this creature dies, it deals 1 damage to each creature and each player.

Sewer Nemesis

As this creature 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.

Cemetery Tampering

Hideaway 5 (When this enchantment enters, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
At the beginning of your upkeep, you may mill three cards. Then if there are twenty or more cards in your graveyard, you may play the exiled card without paying its mana cost.

Tainted Isle

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

Sol Ring

Island

Venomous Hierophant

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When this creature enters, mill three cards. (Put the top three cards of your library into your graveyard.)

Ethereal Investigator

Flying
When this creature enters, investigate X times, where X is the number of opponents you have. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Whenever you draw your second card each turn, create a 1/1 white Spirit creature token with flying.

Juvenile Mist Dragon

Flying
Confounding Clouds — When this creature enters, for each opponent, tap up to one target creature that player controls. Each of those creatures doesn't untap during its controller's next untap step.

Dusk Mangler

As an additional cost to cast this spell, sacrifice a creature, discard a card, or pay 4 life.
When this creature enters, each opponent sacrifices a creature of their choice, discards a card, and loses 4 life.

Raul, Trouble Shooter

Once during each of your turns, you may cast a spell from among cards in your graveyard that were milled this turn.
{T}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Perpetual Timepiece

{T}: Mill two cards.
{2}, Exile this artifact: Shuffle any number of target cards from your graveyard into your library.

Hour of Eternity

Exile X target creature cards from your graveyard. For each card exiled this way, create a token that's a copy of that card, except it's a 4/4 black Zombie.

Deranged Assistant

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

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.)

Liliana, Death Mage

+1: Return up to one target creature card from your graveyard to your hand.
−3: Destroy target creature. Its controller loses 2 life.
−7: Target opponent loses 2 life for each creature card in their graveyard.

Exotic Orchard

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

Ebondeath, Dracolich

Flash
Flying
Ebondeath enters tapped.
You may cast this card from your graveyard if a creature not named Ebondeath, Dracolich died this turn.

Eyeblight Cullers

When this creature dies, create three 1/1 green Elf Warrior creature tokens, then mill three cards. (Put the top three cards of your library into your graveyard.)

Choked Estuary

As this land enters, you may reveal an Island or Swamp card from your hand. If you don't, this land enters tapped.
{T}: Add {U} or {B}.

Mire Triton

Deathtouch
When this creature enters, mill two cards and you gain 2 life. (To mill a card, put the top card of your library into your graveyard.)

Overseer of the Damned

Flying
When this creature enters, you may destroy target creature.
Whenever a nontoken creature an opponent controls dies, create a tapped 2/2 black Zombie creature token.

Crow of Dark Tidings

Flying
When this creature enters or dies, mill two cards. (Put the top two cards of your library into your graveyard.)

Gravebreaker Lamia

Lifelink
When this creature enters, search your library for a card, put it into your graveyard, then shuffle.
Spells you cast from your graveyard cost {1} less to cast.

Thought Scour

Target player mills two cards.
Draw a card.

Atrocious Experiment

Target player mills two cards, draws two cards, and loses 2 life. (To mill a card, a player puts the top card of their library into their graveyard.)

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
This artifact enters with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on this artifact.

Waterfront District

This land enters tapped.
{T}: Add {U} or {B}.
{2}{U}{B}, {T}, Sacrifice this land: Draw a card.

Wharf Infiltrator

Skulk (This creature can't be blocked by creatures with greater power.)
Whenever this creature deals combat damage to a player, you may draw a card. If you do, discard a card.
Whenever you discard a creature card, you may pay {2}. If you do, create a 3/2 colorless Eldrazi Horror creature token.

Massacre Wurm

When this creature enters, creatures your opponents control get -2/-2 until end of turn.
Whenever a creature an opponent controls dies, that player loses 2 life.

Liliana, Defiant Necromancer

+2: Each player discards a card.
−X: Return target nonlegendary creature card with mana value X from your graveyard to the battlefield.
−8: You get an emblem with "Whenever a creature dies, return it to the battlefield under your control at the beginning of the next end step."

Liliana, Heretical Healer

Lifelink
Whenever another nontoken creature you control dies, exile Liliana, Heretical Healer, then return her to the battlefield transformed under her owner's control. If you do, create a 2/2 black Zombie creature token.

Liliana, Heretical Healer // Liliana, Defiant Necromancer

Sphinx of Uthuun

Flying
When this creature enters, reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Sunken Hollow

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

Arcane Signet

Fact or Fiction

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Talisman of Dominance

{T}: Add {C}.
{T}: Add {U} or {B}. This artifact deals 1 damage to you.

Darkwater Catacombs

Spellskite

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

Vile Entomber

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When this creature enters, search your library for a card, put that card into your graveyard, then shuffle.

Liliana, Waker of the Dead

+1: Each player discards a card. Each opponent who can't loses 3 life.
−3: Target creature gets -X/-X until end of turn, where X is the number of cards in your graveyard.
−7: You get an emblem with "At the beginning of combat on your turn, put target creature card from a graveyard onto the battlefield under your control. It gains haste."

Steamcore Scholar

Flying, vigilance
When this creature enters, draw two cards. Then discard two cards unless you discard an instant or sorcery card or a creature card with flying.

Charcoal Diamond

This artifact enters tapped.
{T}: Add {B}.

Grave Titan

Deathtouch
Whenever this creature enters or attacks, create two 2/2 black Zombie creature tokens.

Imprisoned in the Moon

Enchant creature, land, or planeswalker
Enchanted permanent is a colorless land with "{T}: Add {C}" and loses all other card types and abilities.