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.

Dimir Aqueduct

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

Diabolic Tutor

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

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.

Moriok Scavenger

When Moriok Scavenger enters, you may return target artifact creature card from your graveyard to your hand.

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.

Myr Retriever

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.

Dimir Signet

Dismal Backwater

Dismal Backwater enters tapped.
When Dismal Backwater enters, you gain 1 life.
{T}: Add {U} or {B}.

Tower of Murmurs

{8}, {T}: Target player mills eight cards.

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.

Swamp

Wight of Precinct Six

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

Jwar Isle Refuge

Jwar Isle Refuge enters tapped.
When Jwar Isle Refuge enters, you gain 1 life.
{T}: Add {U} or {B}.

Sibsig Host

When Sibsig Host enters, each player mills three cards.

Dimir Guildmage

({U/B} can be paid with either {U} or {B}.)
{3}{U}: Target player draws a card. Activate only as a sorcery.
{3}{B}: Target player discards a card. Activate only as a sorcery.

Graf Rats

At the beginning of combat on your turn, if you both own and control Graf Rats and a creature named Midnight Scavengers, exile them, then meld them into Chittering Host.

Altar of the Brood

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

Decimator Web

{4}, {T}: Target opponent loses 2 life, gets a poison counter, then mills six cards.

Island

Beseech the Queen

({2/B} can be paid with any two mana or with {B}. This card's mana value is 6.)
Search your library for a card with mana value less than or equal to the number of lands you control, reveal it, put it into your hand, then shuffle.

Traumatize

Target player mills half their library, rounded down.

Liliana, the Necromancer

+1: Target player loses 2 life.
−1: Return target creature card from your graveyard to your hand.
−7: Destroy up to two target creatures. Put up to two creature cards from graveyards onto the battlefield under your control.

Dimir Locket

{T}: Add {U} or {B}.
{U/B}{U/B}{U/B}{U/B}, {T}, Sacrifice Dimir Locket: Draw two cards.

Ghoulcaller's Bell

March of the Returned

Return up to two target creature cards from your graveyard to your hand.

Keening Stone

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

Dimir Guildgate

Dimir Guildgate enters tapped.
{T}: Add {U} or {B}.

Vicious Rumors

Vicious Rumors deals 1 damage to each opponent. Each opponent discards a card, then mills a card. You gain 1 life.

Altar of Dementia

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

Macabre Waltz

Return up to two target creature cards from your graveyard to your hand, then discard a card.

Fetid Pools

({T}: Add {U} or {B}.)
Fetid Pools enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Midnight Scavengers

When Midnight Scavengers enters, you may return target creature card with mana value 3 or less from your graveyard to your hand.
(Melds with Graf Rats.)

Grim Harvest

Return target creature card from your graveyard to your hand.
Recover {2}{B} (When a creature is put into your graveyard from the battlefield, you may pay {2}{B}. If you do, return this card from your graveyard to your hand. Otherwise, exile this card.)

Grinding Station

{T}, Sacrifice an artifact: Target player mills three cards.
Whenever an artifact enters, you may untap Grinding Station.

Fleet Swallower

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

Relentless Rats

Relentless Rats gets +1/+1 for each other creature on the battlefield named Relentless Rats.
A deck can have any number of cards named Relentless Rats.