Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

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

{T}: Add {C}.

Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

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.

Draw three cards, then put two cards from your hand on top of your library in any order.

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}.

All creatures get -X/-X until end of turn, where X is the greatest mana value of a commander you own on the battlefield or in the command zone.

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

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

Sacrifice Commander's Sphere: Draw a card.

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.

Creeping Tar Pit enters the battlefield 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.

Whenever an opponent attacks you and/or one or more planeswalkers you control, exile the top card of that player's library. You may play that card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast it.

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

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.

Flying

When Diluvian Primordial enters the battlefield, for each opponent, you may cast up to one target instant or sorcery card from that player's graveyard without paying its mana cost. If a spell cast this way would be put into a graveyard, exile it instead.

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}.

{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}.

Avoidance -- Whenever you cast a noncreature spell, exile up to one target nonland permanent you control, then return that card to the battlefield under its owner's control.

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.

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.

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.

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

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

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Ninjutsu {2}{U}{B} ({2}{U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)

Whenever Fallen Shinobi deals combat damage to a player, that player exiles the top two cards of their library. Until end of turn, you may play those cards without paying their mana costs.

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

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

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.

Destroy target nonartifact creature.

Deathtouch

When Gonti, Lord of Luxury enters the battlefield, look at the top four cards of target opponent's library, exile one of them face down, then put the rest on the bottom of that library in a random order. You may cast that card for as long as it remains exiled, and mana of any type can be spent 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.

When Hostage Taker enters the battlefield, exile another target creature or artifact until Hostage Taker leaves the battlefield. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

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.

Devour Intellect -- When Intellect Devourer enters the battlefield, each opponent exiles a card from their hand until Intellect Devourer leaves the battlefield.

Body Thief -- You may play lands and cast spells from among cards exiled with Intellect Devourer. If you cast a spell this way, you may spend mana as though it were mana of any color to cast it.

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

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

({T}: Add {U}.)

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.

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

Equip {0}

Kicker {3}{U}

Each opponent mills eight cards. If this spell was kicked, instead each opponent mills half their library, rounded up.

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

{T}: Add {U}.

{2}{U}: Put an hour counter on Midnight Clock.

At the beginning of each upkeep, put an hour counter on Midnight Clock.

When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

{T}: Add {C}.

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

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

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.

Ninjutsu {3}{B} ({3}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)

Whenever Nashi, Moon Sage's Scion deals combat damage to a player, exile the top card of each player's library. Until end of turn, you may play one of those cards. If you cast a spell this way, pay life equal to its mana value rather than paying its mana cost.

Counter target noncreature spell.

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

{T}: Add {C}.

{1}{U}{B}, {T}: Target player mills three cards.

Flash

You control your opponents while they're searching their libraries.

While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

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.)

As Phyrexian Revoker enters the battlefield, choose a nonland card name.

Activated abilities of sources with the chosen name can't be activated.

Port of Karfell enters the battlefield tapped.

{T}: Add {U}.

{3}{U}{B}{B}, {T}, Sacrifice Port of Karfell: Mill four cards, then return a creature card from your graveyard to the battlefield tapped. (To mill a card, put the top card of your library into your graveyard.)

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Draw X cards, then discard a card.

Exile target artifact or creature. Its controller creates a 1/1 blue Bird creature token with flying.

Foretell {U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

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

{T}: Add {U}. If you played a land this turn, add {B} instead.

(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.

{T}: Add {C}.

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

Shipwreck Marsh enters the battlefield tapped unless you control two or more other lands.

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

Ninjutsu {4}{U}{B} ({4}{U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)

Whenever Silent-Blade Oni deals combat damage to a player, look at that player's hand. You may cast a spell from among those cards without paying its mana cost.

Look at the top two cards of target opponent's library. Exile one of them face down and put the other on the bottom of that library. You may look at and play the exiled card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast that spell.

Flashback {1}{U}{B}

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.

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

{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 {U} or {B}.)

Sunken Hollow enters the battlefield tapped unless you control two or more basic lands.

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

Each other player discards a card. You draw a card for each card discarded this way.

{T}: Add {C}.

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

{T}: Add {C}.

{T}: Add {U} or {B}. Talisman of Dominance deals 1 damage to you.

Whenever you cast a spell you don't own, create a 3/3 black Demon creature token.

+1: Draw a card. For each opponent, exile up to one target instant or sorcery card from that player's graveyard and put a page counter on it.

-3: You may cast a spell from among cards in exile with page counters on them without paying its mana cost.

Tasha, the Witch Queen can be your commander.

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.)

Temple of Deceit enters the battlefield tapped.

When Temple of Deceit enters the battlefield, scry 1.

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

Flying

Whenever Thief of Sanity deals combat damage to a player, look at the top three cards of that player's library, exile one of them face down, then put the rest into their graveyard. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast it.

You have no maximum hand size.

{T}: Add {C}.

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.

Islandwalk, swampwalk (This creature can't be blocked as long as defending player controls an Island or a Swamp.)

Whenever Wrexial, the Risen Deep deals combat damage to a player, you may cast target instant or sorcery card from that player's graveyard without paying its mana cost. If that spell would be put into a graveyard, exile it instead.

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.)