Horrors you control have menace. Whenever a Horror you control deals combat damage to a player, that player mills that many cards. At the beginning of your end step, choose target artifact or creature card in an opponent's graveyard that was put there from their library this turn. Put it onto the battlefield under your control.

Flying When Carrion Locust enters the battlefield, exile target card from an opponent's graveyard. If it was a creature card, that player loses 1 life.

Menace At the beginning of your precombat main phase, you may sacrifice a creature. When you do, choose a nonland card name, then target player reveals their hand and discards all cards with that name.

As an additional cost to cast this spell, sacrifice a creature. Draw two cards.

Flying, deathtouch When Baleful Strix enters the battlefield, draw a card.

Target player draws two cards and loses 2 life.

Draw two cards. Then discard a card unless you attacked this turn.

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.) Draw a card.

Skulk (This creature can't be blocked by creatures with greater power.) At the beginning of your upkeep, you may discard all the cards in your hand. If you do, draw that many cards.

As Icon of Ancestry enters the battlefield, choose a creature type. Creatures you control of the chosen type get +1/+1. {3}, {T}: Look at the top three cards of your library. You may reveal a creature card of the chosen type from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Draw X cards.

Scry 1. Draw a card.

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

Flying When Psychic Symbiont enters the battlefield, target opponent discards a card and you draw a card.

Bad River enters the battlefield tapped. {T}, Sacrifice Bad River: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

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

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

({T}: Add {U}.)

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

({T}: Add {B}.)

{T}: Add {C}{C}. Activate only if you control five or more lands.

({T}: Add {U} or {B}.)

+2: Exile the top three cards of target opponent's library. −X: Put a creature card with mana value X exiled with Ashiok, Nightmare Weaver onto the battlefield under your control. That creature is a Nightmare in addition to its other types. −10: Exile all cards from all opponents' hands and graveyards.

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.

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.

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

Target opponent mills seven cards.

At the beginning of your upkeep, scry 1. Whenever you discard a card, each opponent mills two cards. (They put the top two cards of their library into their graveyard.)

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

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

When Ravenous Gigamole enters the battlefield, mill three cards. You may put a creature card from among the cards milled this way into your hand. If you don't, put a +1/+1 counter on Ravenous Gigamole. (To mill a card, put the top card of your library into your graveyard.)

Flying Whenever you attack with one or more creatures, target player mills that many cards. (To mill a card, a player puts the top card of their library into their graveyard.) {2}{U}: Put Screaming Swarm from your graveyard into your library second from the top.

Whenever you draw a card, target opponent mills two cards. If two nonland cards that share a color were milled this way, repeat this process. {5}{U}: Draw a card, then discard a card.

When Teferi's Tutelage enters the battlefield, draw a card, then discard a card. Whenever you draw a card, target opponent mills two cards. (They put the top two cards of their library into their graveyard.)

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

Black creature spells you cast cost {1} less to cast. Whenever you cast a creature spell, each opponent loses 1 life and you gain 1 life.

Aberrant Tinkering — When Grell Philosopher enters the battlefield and at the beginning of your upkeep, each Horror you control gains all activated abilities of target artifact an opponent controls until end of turn. You may spend blue mana as though it were mana of any color to activate those abilities.

As Herald's Horn enters the battlefield, choose a creature type. Creature spells you cast of the chosen type cost {1} less to cast. At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

As Heraldic Banner enters the battlefield, choose a color. Creatures you control of the chosen color get +1/+0. {T}: Add one mana of the chosen color.

{T}, Sacrifice Jeweled Lotus: Add three mana of any one color. Spend this mana only to cast your commander.

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you. {T}: Add {C}{C}.

{T}: Add {C}. {1}, {T}, Sacrifice Mind Stone: Draw a card.

When Abyssal Gatekeeper dies, each player sacrifices a creature.

Counter target artifact or enchantment spell.

Counter target creature or planeswalker spell unless its controller pays {2}. If an opponent has eight or more cards in their graveyard, instead counter that spell, then scry 2.

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.")

When Dinrova Horror enters the battlefield, return target permanent to its owner's hand, then that player discards a card.

If it's not your turn, you may exile a black card from your hand rather than pay this spell's mana cost. Destroy all creatures that entered the battlefield this turn.

Flash This spell can't be countered. Whenever you cast a spell, choose up to one — • Return target spell you don't control to its owner's hand. • Return target nonland permanent to its owner's hand.

Destroy target creature. You lose 2 life.

Choose a creature type. Destroy all creatures that aren't of the chosen type.

Dominate Monster — When Mind Flayer enters the battlefield, gain control of target creature for as long as you control Mind Flayer.

Plague Mare can't be blocked by white creatures. When Plague Mare enters the battlefield, creatures your opponents control get -1/-1 until end of turn.

Whenever Sludge Monster enters the battlefield or attacks, put a slime counter on up to one other target creature. Non-Horror creatures with slime counters on them lose all abilities and have base power and toughness 2/2.

Flying At the beginning of your end step, exile the top card of each opponent's library. You may play those 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. Whenever a nonland permanent an opponent owns enters the battlefield under your control, they lose life equal to its mana value.

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

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.