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

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

Sacrifice a creature: Add {C}{C}.

Whenever a creature dies, put a +1/+1 counter on equipped creature. If equipped creature is a Vampire, put two +1/+1 counters on it instead. Equip {1}

{T}, Sacrifice a creature: Blasting Station deals 1 damage to any target. Whenever a creature enters the battlefield, you may untap Blasting Station.

{T}: Choose any number of target creatures. Each of those creatures gains persist until end of turn. (When it 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.)

Equipped creature gets +2/+2. Whenever equipped creature dies, you may put a creature card from your hand onto the battlefield and attach Deathrender to it. Equip {2}

Whenever a nontoken creature you control dies, put a charge counter on Lightning Coils. At the beginning of your upkeep, if Lightning Coils has five or more charge counters on it, remove all of them from it and create that many 3/1 red Elemental creature tokens with haste. Exile them at the beginning of the next end step.

{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.

Equipped creature gets +2/+2, has intimidate, and is a black Zombie. (A creature with intimidate can't be blocked except by artifact creatures and/or creatures that share a color with it.) Whenever a nontoken creature is put into your graveyard from the battlefield, you may pay {4}. If you do, return that card to the battlefield and attach Nim Deathmantle to it. Equip {4}

Blue spells you cast cost {1} less to cast.

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

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

Sacrifice a creature: Put a charge counter on Spawning Pit. {1}, Remove two charge counters from Spawning Pit: Create a 2/2 colorless Spawn artifact creature token.

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

You may choose not to untap Vedalken Shackles during your untap step. {2}, {T}: Gain control of target creature with power less than or equal to the number of Islands you control for as long as Vedalken Shackles remains tapped.

Flying When Aura Thief dies, you gain control of all enchantments. (You don't get to move Auras.)

You may have Body Double enter the battlefield as a copy of any creature card in a graveyard.

{3}, Sacrifice Burnished Hart: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

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.)

Flying Whenever a nontoken creature enters the battlefield under an opponent's control, create a token that's a copy of that creature except it's an artifact in addition to its other types. Then exile all other tokens created with Faerie Artisans.

When Floating-Dream Zubera dies, draw a card for each Zubera that died this turn.

Defender (This creature can't attack.) When Floodgate has flying, sacrifice it. When Floodgate leaves the battlefield, it deals damage equal to half the number of Islands you control, rounded down, to each nonblue creature without flying.

Flying When Iridescent Drake enters the battlefield, put target Aura card from a graveyard onto the battlefield under your control attached to Iridescent Drake.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.) When Jeskai Sage dies, draw a card.

Flying When Keiga, the Tide Star dies, gain control of target creature.

Whenever you draw your second card each turn, create a 1/1 blue Illusion creature token with "This creature gets +1/+0 for each other Illusion you control." Whenever an Illusion you control dies, you may put a permanent card with mana value less than or equal to that creature's power from your hand onto the battlefield.

Flying When Mulldrifter enters the battlefield, draw two cards. Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters the battlefield.)

Flying Whenever another creature dies, you may draw a card. If you do, discard a card.

Whenever you draw a card, you may pay {1}. If you do, put a +1/+1 counter on Nadir Kraken and create a 1/1 blue Tentacle creature token.

Flash When Naru Meha, Master Wizard enters the battlefield, copy target instant or sorcery spell you control. You may choose new targets for the copy. Other Wizards you control get +1/+1.

When Oculus dies, you may draw a card.

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.

Flying When Palace Familiar dies, draw a card.

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand. Whenever you draw a card, each opponent loses 1 life.

When Reef Worm dies, create a 3/3 blue Fish creature token with "When this creature dies, create a 6/6 blue Whale creature token with 'When this creature dies, create a 9/9 blue Kraken creature token.'"

Whenever River Kelpie or another permanent enters the battlefield from a graveyard, draw a card. Whenever a player casts a spell from a graveyard, draw a card. Persist (When this creature 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.)

Sacrifice Salvager of Ruin: Choose target permanent card in your graveyard that was put there from the battlefield this turn. Return it to your hand.

Whenever Selhoff Occultist or another creature dies, target player mills a card.

Exploit (When this creature enters the battlefield, you may sacrifice a creature.) When Sidisi's Faithful exploits a creature, return target creature to its owner's hand.

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle. When Solemn Simulacrum dies, you may draw a card.

When Specimen Collector enters the battlefield, create a 1/1 green Squirrel creature token and a 0/3 blue Crab creature token. When Specimen Collector dies, create a token that's a copy of target token you control.

{1}{U}, {T}: Create a 2/2 blue Homunculus creature token, then sacrifice a creature.

Flying When Surveilling Sprite dies, you may draw a card.

When Thassa's Oracle enters the battlefield, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Partner with Pir, Imaginative Rascal (When this creature enters the battlefield, target player may put Pir into their hand from their library, then shuffle.) Whenever you draw a card, put a +1/+1 counter on Toothy, Imaginary Friend. When Toothy leaves the battlefield, draw a card for each +1/+1 counter on it.

Hideaway 4 (When this creature enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.) Watcher for Tomorrow enters the battlefield tapped. When Watcher for Tomorrow leaves the battlefield, put the exiled card into its owner's hand.

When Whirler Rogue enters the battlefield, create two 1/1 colorless Thopter artifact creature tokens with flying. Tap two untapped artifacts you control: Target creature can't be blocked this turn.

Enchant creature When enchanted creature dies, return that card to the battlefield under your control.

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

Create a token that's a copy of target creature you control. Flashback {5}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Return all creatures to their owners' hands.

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

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

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

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.)

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

{T}: Add {C}. {3}, {T}, Sacrifice Haunted Fengraf: Return a creature card at random from your graveyard to your hand.

{T}: Add {C}. {T}, Sacrifice a creature: You gain 1 life.

({T}: Add {U}.)

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.

{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.

Look at the top seven cards of your library. You may put one of those cards onto the battlefield if it has the same name as a permanent. Put the rest on the bottom of your library in any order.

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.)