If an artifact or creature entering the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Flash When Silver Shroud Costume enters the battlefield, attach it to target creature you control. That creature gains shroud until end of turn. (It can't be the target of spells or abilities.) Equipped creature can't be blocked. Equip {3}

Exile up to two target creatures you control, then return those cards to the battlefield under their owner's control.

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.

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.

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

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.

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

Ward {2} As Roaming Throne enters the battlefield, choose a creature type. Roaming Throne is the chosen type in addition to its other types. If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Whenever a Swamp enters the battlefield under your control, choose one — • You draw a card and you lose 1 life. • Dread Presence deals 2 damage to any target and you gain 2 life.

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

When Phyrexian Rager enters the battlefield, you draw a card and you lose 1 life.

Target player draws two cards and loses 2 life.

Devoid (This card has no color.) Whenever a land enters the battlefield under an opponent's control, that player exiles the top two cards of their library and you draw two cards.

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.

Enchant creature Enchanted creature gets +1/+0 and can't be blocked.

Enchant creature Enchanted creature can't be blocked. Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

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

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

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

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

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

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

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

({T}: Add {U}.)

Minas Morgul, Dark Fortress enters the battlefield tapped. {T}: Add {B}. {3}{B}, {T}: Put a shadow counter on target creature. For as long as that creature has a shadow counter on it, it's a Wraith in addition to its other types. (A creature with shadow can block or be blocked by only creatures with shadow.)

Morphic Pool enters the battlefield tapped unless you have two or more opponents. {T}: Add {U} or {B}.

Myriad Landscape enters the battlefield 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.

Path of Ancestry enters the battlefield 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.)

Pit of Offerings enters the battlefield tapped. When Pit of Offerings enters the battlefield, exile up to three target cards from graveyards. {T}: Add {C}. {T}: Add one mana of any of the exiled cards' colors.

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

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

({T}: Add {B}.)

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

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.

+1: Create a 2/3 blue and black Nightmare creature token with "Whenever this creature attacks or blocks, each opponent exiles the top two cards of their library." −3: Return target nonland permanent to its owner's hand, then that player exiles a card from their hand. −7: You may cast up to three spells from among face-up cards your opponents own from exile without paying their mana costs.

Each opponent exiles cards from the top of their library until that player has exiled cards with total mana value 20 or more.

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.) Equip {0}

Target creature gains deathtouch and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

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

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

Add {B}{B}{B}.

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.

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

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.

You may cast Eternal Scourge from exile. When Eternal Scourge becomes the target of a spell or ability an opponent controls, exile Eternal Scourge.

When Haunt of the Dead Marshes enters the battlefield, scry 1. {2}{B}: Return Haunt of the Dead Marshes from your graveyard to the battlefield tapped. Activate only if you control a legendary creature.

Counter target spell.

Exile X target creatures. For each creature exiled this way, its controller creates a 2/2 green Boar creature token.

Choose odd or even. Exile each creature with mana value of the chosen quality. (Zero is even.)

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

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.

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

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

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

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

{T}: Target player exiles a card from their graveyard. {1}, Exile Relic of Progenitus: Exile all graveyards. Draw a card.

Shadow (This creature can block or be blocked by only creatures with shadow.) If a card would be put into an opponent's graveyard from anywhere, instead exile it with a void counter on it. {T}, Sacrifice Dauthi Voidwalker: Choose an exiled card an opponent owns with a void counter on it. You may play it this turn without paying its mana cost.

If Leyline of the Void is in your opening hand, you may begin the game with it on the battlefield. If a card would be put into an opponent's graveyard from anywhere, exile it instead.

Whenever you attack, up to one target attacking creature can't be blocked this turn. Return that creature to its owner's hand at the beginning of the next end step. Choose a Background (You can have a Background as a second commander.)

Target creature becomes black and gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.) Draw a card.

Equipped creature has deathtouch and lifelink. Equip {2}

Haste Whenever Bessie attacks, another target legendary creature can't be blocked this turn. Crew 2 (Tap any number of creatures you control with total power 2 or more: This Vehicle becomes an artifact creature until end of turn.)

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.)

Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

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.

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.

When Lantern of the Lost enters the battlefield, exile target card from a graveyard. {1}, {T}, Exile Lantern of the Lost: Exile all cards from all graveyards, then draw a card.

Choose target creature you control. Destroy all creatures with power less than that creature's power.

Put target creature card from an opponent's graveyard onto the battlefield tapped under your control, then exile that player's graveyard.

When you cast this spell, target opponent exiles the top four cards of their library, then you may put any number of land cards that player owns from exile onto the battlefield under your control.

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.

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

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

(Gain the next level as a sorcery to add its ability.) Whenever a creature you control deals combat damage to a player, exile the top card of that player's library face down. You may look at it for as long as it remains exiled. {1}{U}{B}: Level 2 Creatures you control have menace. {2}{U}{B}: Level 3 You may play cards exiled with Rogue Class, and you may spend mana as though it were mana of any color to cast those spells.

Equipped creature gets +1/+1 and has trample and lifelink. {1}: Permanents your opponents control lose hexproof and indestructible until end of turn. Equip {2}

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.

You may have Spark Double enter the battlefield as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

Choose one. If you control a commander as you cast this spell, you may choose both. • Each opponent sacrifices a creature they control with the greatest power. • Exile all opponents' graveyards, then create X 0/1 black Thrull creature tokens, where X is the greatest power among creature cards exiled this way.