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

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

{1}, {T}: Add {U}{B}.

{3}, {T}: Double the amount of each type of unspent mana you have.

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

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

{T}: Add {C}{C}.

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

Flash Ward {2} Probing Telepathy — Whenever a creature entering the battlefield under an opponent's control causes a triggered ability of that creature to trigger, you may copy that ability. You may choose new targets for the copy.

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.

Menace As an additional cost to cast black permanent spells, you may pay 2 life. Those spells cost {B} less to cast if you paid life this way. This effect reduces only the amount of black mana you pay. Whenever you cast a black permanent spell, target creature you control gets +1/+1 and gains menace until end of turn.

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.

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.

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.) Whenever Guiltfeeder attacks and isn't blocked, defending player loses 1 life for each card in their graveyard.

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

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

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.

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

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

As Phyrexian Revoker enters the battlefield, choose a nonland card name. Activated abilities of sources with the chosen name can't be activated.

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

As Sewer Nemesis enters the battlefield, 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.

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.

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.)

At the beginning of each end step, put a slime counter on each creature you don't control. Creatures you don't control get -1/-1 for each slime counter on them. Whenever a creature you don't control with a slime counter on it dies, create a 1/1 black Slug creature token. {U}{B}, Sacrifice a Slug: Draw a card.

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.

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

Whenever a creature dies, put a charge counter on Black Market. At the beginning of your precombat main phase, add {B} for each charge counter on Black Market.

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.

As Cover of Darkness enters the battlefield, choose a creature type. Creatures of the chosen type have fear. (They can't be blocked except by artifact creatures and/or black creatures.)

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.

Commander creatures you own have "Whenever this creature becomes tapped, it and other creatures you control that share a creature type with it each get +2/+0 and gain undying until end of turn." (When a creature with undying dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

As Kindred Discovery enters the battlefield, choose a creature type. Whenever a creature you control of the chosen type enters the battlefield or attacks, draw a card.

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield. You may cast spells as though they had flash.

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

As Reflections of Littjara enters the battlefield, choose a creature type. Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

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.")

If you control a commander, you may cast this spell without paying its mana cost. Exile target creature.

Choose one. If you control a commander as you cast this spell, you may choose both. • Target player draws X cards. • Target player mills twice X cards.

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.

If you control a commander, you may cast this spell without paying its mana cost. Counter target noncreature spell.

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost. Counter target spell.

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

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

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

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

Castle Locthwain enters the battlefield tapped unless you control a Swamp. {T}: Add {B}. {1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.

Castle Vantress enters the battlefield tapped unless you control an Island. {T}: Add {U}. {2}{U}{U}, {T}: Scry 2.

{T}: Add {C}. {T}, Sacrifice Command Beacon: Put your commander into your hand from the command zone.

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

({T}: Add {U}.)

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

({T}: Add {U}.) Mystic Sanctuary enters the battlefield tapped unless you control three or more other Islands. When Mystic Sanctuary enters the battlefield untapped, you may put target instant or sorcery card from your graveyard on top of your library.

{T}: Add {C}. {2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

{T}: Add {U}. Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

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

{T}: Add {B}. {B}, {T}: Target legendary creature gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)

({T}: Add {B}.)

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

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.

Target opponent chooses a number. You may have that player lose that much life. If you don't, that player sacrifices all but that many permanents.

Choose a creature type. Creatures that aren't of the chosen type get -3/-3 until end of turn.

Destroy all creatures. They can't be regenerated.

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

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

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

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.

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

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

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

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

Look at the top three cards of your library, then put them back in any order. You may shuffle. Draw a card.

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

Put all creature cards from all graveyards onto the battlefield under your control.