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

At the beginning of each upkeep, untap all creatures and lands.

Whenever you cast a creature spell, draw a card.

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.)

Lands you control have "{T}: Add one mana of any color."

{T}: Add one mana of any color.

As Cloud Key enters the battlefield, choose artifact, creature, enchantment, instant, or sorcery.

Spells you cast of the chosen type cost {1} less to cast.

As an additional cost to cast this spell, sacrifice a creature.

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

Flash

Whenever a creature you control dies, each opponent sacrifices a creature.

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Put any number of target creature cards from your graveyard on top of your library.

Draw a card.

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

({T}: Add {G}.)

{T}: Add three mana of any one color.

Put any number of target creature cards from your graveyard on top of your library.

Draw a card.

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

{2}, {T}, Sacrifice Hedron Archive: Draw two cards.

({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}.)

({T}: Add {U}.)

({T}: Add {U}.)

Face-down creatures get +1/+1.

{2}{U}: Turn target face-down creature face up.

As Ixidron enters the battlefield, turn all other nontoken creatures face down. (They're 2/2 creatures.)

Ixidron's power and toughness are each equal to the number of face-down creatures on the battlefield.

If you would draw a card while your library has no cards in it, you win the game instead.

+1: Target player mills two cards. Draw a card.

-8: Draw seven cards. Then if your library has no cards in it, you win the game.

The first face-down creature spell you cast each turn costs {3} less to cast.

Whenever a face-down creature enters the battlefield under your control, 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.

You may look at the top card of your library any time.

You may cast artifact spells and colorless spells from the top of your library.

{T}, Pay 1 life: Exile the top card of your library.

Face-down creature spells you cast cost {1} less to cast.

{1}{G}: Turn Obscuring Aether face down. (It becomes a 2/2 creature.)

Sacrifice a creature: Add one mana of any color.

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.

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Face-down creatures you control get +0/+1.

Whenever a permanent you control is turned face up, draw a card.

Untap all permanents you control during each other player's untap step.

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

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.

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

({T}: Add {B}.)

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)

Equip {1}

When Thassa's Oracle enters, 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.)

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

Whenever a face-down creature enters the battlefield under your control, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Whenever a permanent you control is turned face up, if it's a creature, it gets +2/+2 until end of turn.

Colorless spells you cast cost {2} less to cast.

+1: Exile the top card of your library face down and look at it. Create a 2/2 colorless Spirit creature token. When that token leaves the battlefield, put the exiled card into your hand.

-3: Destroy target permanent that's one or more colors.

You may cast creature spells as though they had flash.

+1: Until your next turn, up to one target creature gains vigilance and reach.

-2: Look at the top three cards of your library. Exile one face down and put the rest on the bottom of your library in any order. For as long as it remains exiled, you may look at that card and you may cast it if it's a creature spell.

You may look at the top card of your library any time.

You may cast creature spells from the top of your library.

You may spend mana as though it were mana of any type to cast creature spells.