Captain N'ghathrod

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.

Dark Revenant

Flying
When Dark Revenant dies, put it on top of its owner's library.

Gloom Sower

Whenever Gloom Sower becomes blocked by a creature, that creature's controller loses 2 life and you gain 2 life.

Nighthowler

Bestow {2}{B}{B} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Nighthowler and enchanted creature each get +X/+X, where X is the number of creature cards in all graveyards.

Mage Hunters' Onslaught

Destroy target creature or planeswalker.
Whenever a creature blocks this turn, its controller loses 1 life.

Mage Hunter

Whenever an opponent casts or copies an instant or sorcery spell, they lose 1 life.

Infectious Horror

Whenever Infectious Horror attacks, each opponent loses 2 life.

Foul-Tongue Shriek

Target opponent loses 1 life for each attacking creature you control. You gain that much life.

Grim Guardian

Constellation — Whenever Grim Guardian or another enchantment you control enters, each opponent loses 1 life.

Doom Weaver

Reach
Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Doom Weaver is paired with another creature, each of those creatures has "When this creature dies, draw cards equal to its power."

Testament Bearer

When Testament Bearer dies, look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Laquatus's Champion

When Laquatus's Champion enters, target player loses 6 life.
When Laquatus's Champion leaves the battlefield, that player gains 6 life.
{B}: Regenerate Laquatus's Champion.

Necropolis Regent

Flying
Whenever a creature you control deals combat damage to a player, put that many +1/+1 counters on it.

Archetype of Imagination

Creatures you control have flying.
Creatures your opponents control lose flying and can't have or gain flying.

Time Reaper

Flying, haste
Consume Anomaly — Whenever Time Reaper deals combat damage to a player, put target face-up card they own in exile on the bottom of their library. If you do, you gain 3 life.

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.)

Vashta Nerada

Indestructible
Shadow (This creature can block or be blocked by only creatures with shadow.)
Morbid — At the beginning of each end step, if a creature died this turn, put a +1/+1 counter on Vashta Nerada.

Thassa, God of the Sea

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)
At the beginning of your upkeep, scry 1.
{1}{U}: Target creature you control can't be blocked this turn.

Horrid Shadowspinner

Lifelink
Whenever Horrid Shadowspinner attacks, you may draw cards equal to its power. If you do, discard that many cards.

Grazilaxx, Illithid Scholar

Whenever a creature you control becomes blocked, you may return it to its owner's hand.
Whenever one or more creatures you control deal combat damage to a player, draw a card.

Wharf Infiltrator

Skulk (This creature can't be blocked by creatures with greater power.)
Whenever Wharf Infiltrator 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.

Stealer of Secrets

Whenever Stealer of Secrets deals combat damage to a player, draw a card.

Hell's Caretaker

{T}, Sacrifice a creature: Return target creature card from your graveyard to the battlefield. Activate only during your upkeep.

Ravenous Chupacabra

When Ravenous Chupacabra enters, destroy target creature an opponent controls.

Phyrexian Obliterator

Trample
Whenever a source deals damage to Phyrexian Obliterator, that source's controller sacrifices that many permanents.

Overcharged Amalgam

Flash
Flying
Exploit (When this creature enters, you may sacrifice a creature.)
When Overcharged Amalgam exploits a creature, counter target spell, activated ability, or triggered ability.

Elder Brain

Menace
Whenever Elder Brain 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.

Dread Slaver

Whenever a creature dealt damage by Dread Slaver this turn dies, return it to the battlefield under your control. That creature is a black Zombie in addition to its other colors and types.

Brainstealer Dragon

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.

Archetype of Finality

Creatures you control have deathtouch.
Creatures your opponents control lose deathtouch and can't have or gain deathtouch.

Dutiful Attendant

When Dutiful Attendant dies, return another target creature card from your graveyard to your hand.

Hunted Horror

Trample
When Hunted Horror enters, target opponent creates two 3/3 green Centaur creature tokens with protection from black.

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 Uchuulon.

Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on Chasm Skulker.
When Chasm Skulker dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on Chasm Skulker. (They can't be blocked as long as defending player controls an Island.)

Sludge Monster

Whenever Sludge Monster enters 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.

Jace's Phantasm

Flying
Jace's Phantasm gets +4/+4 as long as an opponent has ten or more cards in their graveyard.

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.

Umbris, Fear Manifest

Umbris, Fear Manifest gets +1/+1 for each card your opponents own in exile.
Whenever Umbris or another Nightmare or Horror you control enters, target opponent exiles cards from the top of their library until they exile a land card.

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.

Nemesis of Reason

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

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.)

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.

Fated Infatuation

Create a token that's a copy of target creature you control. If it's your turn, scry 2.

Essence Harvest

Target player loses X life and you gain X life, where X is the greatest power among creatures you control.

Nullify

Prowler's Helm

Equipped creature can't be blocked except by Walls.
Equip {2}

Claim of Erebos

Enchant creature
Enchanted creature has "{1}{B}, {T}: Target player loses 2 life."

Banewasp Affliction

Enchant creature
When enchanted creature dies, that creature's controller loses life equal to its toughness.

Font of Fortunes

{1}{U}, Sacrifice Font of Fortunes: Draw two cards.

Soul Ransom

Enchant creature
You control enchanted creature.
Discard two cards: Soul Ransom's controller sacrifices it, then draws two cards. Only your opponents may activate this ability.

Sol Ring

Dimir Charm

Choose one —
• Counter target sorcery spell.
• Destroy target creature with power 2 or less.
• Look at the top three cards of target player's library. Put one back and the rest into that player's graveyard.

Confiscate

Enchant permanent
You control enchanted permanent.

Cancel

Font of Return

{3}{B}, Sacrifice Font of Return: Return up to three target creature cards from your graveyard to your hand.

Spiteful Blow

Call of the Nightwing

Create a 1/1 blue and black Horror creature token with flying.
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.)

Endless Evil

Enchant creature you control
At the beginning of your upkeep, create a token that's a copy of enchanted creature, except the token is 1/1.
When enchanted creature dies, if that creature was a Horror, return Endless Evil to its owner's hand.

Curse of Disturbance

Enchant player
Whenever enchanted player is attacked, create a 2/2 black Zombie creature token. Each opponent attacking that player does the same.

Gravepurge

Put any number of target creature cards from your graveyard on top of your library.
Draw a card.

Murder

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.

Pristine Talisman

Island

Leechridden Swamp

({T}: Add {B}.)
Leechridden Swamp enters tapped.
{B}, {T}: Each opponent loses 1 life. Activate only if you control two or more black permanents.

Swamp

Unknown Shores

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Bojuka Bog

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

Temple of the False God

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

Command Tower

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

Myriad Landscape

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

Creeping Tar Pit

Creeping Tar Pit enters tapped.
{T}: Add {U} or {B}.
{1}{U}{B}: Creeping Tar Pit becomes a 3/2 blue and black Elemental creature until end of turn and can't be blocked this turn. It's still a land.

Drowned Catacomb

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

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Sunken Hollow

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

Choked Estuary

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

Temple of Deceit

Temple of Deceit enters tapped.
When Temple of Deceit enters, scry 1.
{T}: Add {U} or {B}.

Watery Grave

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