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.)

This land enters tapped. When this land enters, exile target player's graveyard. {T}: Add {B}.

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

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

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

This land enters tapped. {T}: Add {U} or {B}. {1}{U}{B}: This land 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.

This land enters tapped. When this land enters, return a land you control to its owner's hand. {T}: Add {U}{B}.

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

({T}: Add {U}.)

This land enters tapped unless you have two or more opponents. {T}: Add {U} or {B}.

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

This land 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.)

{T}, Pay 1 life, Sacrifice this land: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

This land enters tapped. {T}: Add {U}. {3}{U}{B}{B}, {T}, Sacrifice this land: 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.)

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

({T}: Add {U} or {B}.) This land enters 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.

This land enters tapped. When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.) {T}: Add {U} or {B}.

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

Whenever another permanent you control enters, each opponent mills a card.

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

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

Players have no maximum hand size. {X}{X}, {T}: Each player draws X cards. {2}{U}, {T}: Each opponent mills cards equal to the number of cards in their hand.

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

Whenever a permanent becomes untapped, that permanent's controller mills a card.

{T}: Add {C}. {1}, {T}, Sacrifice this artifact: Draw a card.

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

Equipped creature gets +1/-1. Whenever equipped creature dies, draw two cards. Equip {1}

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

{T}: Add {C}. {T}: Add {U} or {B}. This artifact deals 1 damage to you.

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.

Flash Ward {2} Probing Telepathy — Whenever a creature entering 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.

If an opponent would mill one or more cards, they mill twice that many cards instead. (To mill a card, a player puts the top card of their library into their graveyard.)

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.

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

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.

At the beginning of each player's upkeep, that player mills X cards, where X is the number of cards in their hand.

{1}{U}{B}: Whenever a card is put into an opponent's graveyard from anywhere this turn, that player loses 1 life. {2}{U}{B}: Target player mills two cards.

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.

Aberrant Tinkering — When this creature enters 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.

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

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 this creature enters, gain control of target creature for as long as you control this creature.

Whenever this creature attacks, defending player mills ten cards.

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

Indestructible As long as your devotion to blue and black is less than seven, Phenax isn't a creature. Creatures you control have "{T}: Target player mills X cards, where X is this creature's toughness."

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

When this creature enters, destroy target creature an opponent controls.

Landfall — Whenever a land you control enters, each opponent mills three cards. (To mill a card, a player puts the top card of their library into their graveyard.)

Flash At the beginning of your upkeep, each player mills three cards. You may exile a creature card from among the cards milled this way. If you do, this creature becomes a copy of that card, except it has this ability.

Whenever this creature 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.

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

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 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.)

Umbris 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.

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

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

Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell and you may choose a new target for the copy.) Target player mills half their library, rounded down.

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 this card, 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.

Replicate—Tap an untapped Horror you control. (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.) Exile target instant or sorcery card from a graveyard and copy it. You may cast the copy without paying its mana cost. Exile Psionic Ritual.

When this enchantment enters, you become the monarch. At the beginning of your upkeep, any number of target players each mill two cards. If you're the monarch, each of those players mills ten cards instead. (To mill a card, a player puts the top card of their library into their graveyard.)

As this enchantment enters, choose a creature type. Whenever a creature you control of the chosen type enters or attacks, draw a card.

Whenever an opponent casts a spell, that player mills two cards.

Enchant creature {U}: Untap enchanted creature. {U}: Enchanted creature gains flying until end of turn. {U}: Enchanted creature gains shroud until end of turn. (It can't be the target of spells or abilities.) {1}: Enchanted creature gets +1/-1 or -1/+1 until end of turn.

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

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep. You draw a card at the beginning of the next turn's upkeep.

Counter target spell.

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.

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.

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