Creatures you control have flying. Creatures your opponents control lose flying and can't have or gain flying.

When Brinelin, the Moon Kraken enters the battlefield or whenever you cast a spell with mana value 6 or greater, you may return target nonland permanent to its owner's hand. Partner (You can have two commanders if both have partner.)

Companion — Your starting deck contains only cards with even mana values. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.) When Gyruda enters the battlefield, each player mills four cards. Put a creature card with an even mana value from among the milled cards onto the battlefield under your control.

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.

This spell costs {1} less to cast for each snow land you control. When Icebreaker Kraken enters the battlefield, artifacts and creatures target opponent controls don't untap during that player's next untap step. Return three snow lands you control to their owner's hand: Return Icebreaker Kraken to its owner's hand.

Affinity for tokens (This spell costs {1} less to cast for each token you control.) Whenever a token enters the battlefield under your control, tap target nonland permanent an opponent controls. It doesn't untap during its controller's next untap step.

Flash {U}, Sacrifice an Island: Lochmere Serpent can't be blocked this turn. {B}, Sacrifice a Swamp: You gain 1 life and draw a card. {U}{B}: Exile five target cards from an opponent's graveyard. Return Lochmere Serpent from your graveyard to your hand. Activate only as a sorcery.

When Massacre Wurm enters the battlefield, creatures your opponents control get -2/-2 until end of turn. Whenever a creature an opponent controls dies, that player loses 2 life.

Menace When Noxious Gearhulk enters the battlefield, you may destroy another target creature. If a creature is destroyed this way, you gain life equal to its toughness.

When Scourge of Fleets enters the battlefield, return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.

Krakens, Leviathans, Octopuses, and Serpents you control can't be blocked except by Krakens, Leviathans, Octopuses, and Serpents.

Whenever a Kraken, Leviathan, Octopus, or Serpent you control deals combat damage to a player, create a 9/9 blue Kraken creature token.

If you control a commander, you may cast this spell without paying its mana cost. Counter target noncreature spell.

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost. Counter target spell.

Counter target spell. At the beginning of your next main phase, add an amount of {C} equal to that spell's mana value.

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

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

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

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

({T}: Add {U} or {B}.) Ice Tunnel enters the battlefield tapped.

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

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

{T}, Pay 1 life, Sacrifice Prismatic Vista: Search your library for a basic land card, put it onto the battlefield, then shuffle.

({T}: Add {U}.)

({T}: Add {B}.)

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

{T}: Add {C}. {U/B}, {T}: Add {U}{U}, {U}{B}, or {B}{B}.

Each land is a Swamp in addition to its other land types.

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

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

{T}: Add one mana of any color in your commander's color identity. Sacrifice Commander's Sphere: Draw a card.

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

Creature spells you cast cost {2} less to cast. Creatures you control get -1/-1.

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you. {T}: Add {C}{C}.

Mana Vault doesn't untap during your untap step. At the beginning of your upkeep, you may pay {4}. If you do, untap Mana Vault. At the beginning of your draw step, if Mana Vault is tapped, it deals 1 damage to you. {T}: Add {C}{C}{C}.

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

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.

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

Return target nonland permanent you don't control to its owner's hand. Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

If you control a commander, you may cast this spell without paying its mana cost. Exile target creature.

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

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

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Exploit (When this creature enters the battlefield, you may sacrifice a creature.) When Rot-Tide Gargantua exploits a creature, each opponent sacrifices a creature.

As an additional cost to cast this spell, pay X life. All creatures get -X/-X until end of turn.

Creatures you control are every creature type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield. {3}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

At the beginning of your upkeep, you may look at the top card of your library. If it's a creature card, you may reveal it and put a quest counter on Quest for Ula's Temple. At the beginning of each end step, if there are three or more quest counters on Quest for Ula's Temple, you may put a Kraken, Leviathan, Octopus, or Serpent creature card from your hand onto the battlefield.

{4}, {T}: You may put a creature card from your hand onto the battlefield.

You may have Sakashima of a Thousand Faces enter the battlefield as a copy of another creature you control, except it has Sakashima of a Thousand Faces's other abilities. The "legend rule" doesn't apply to permanents you control. Partner (You can have two commanders if both have partner.)

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.

Hexproof Lieutenant — As long as you control your commander, Stormsurge Kraken gets +2/+2 and has "Whenever Stormsurge Kraken becomes blocked, you may draw two cards."

You may look at the top card of your library any time. You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost. {T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

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

You draw two cards and you lose 2 life.

Look at the top three cards of your library, then put them back in any order. You may shuffle. Draw a card.

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Mutate {1}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.) Flash Whenever this creature deals combat damage to a player, draw a card.

Draw cards equal to the number of cards in your hand, then discard a card for each card drawn this way. Basic landcycling {2} ({2}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Draw two cards, then discard two cards.

Look at the top four cards of your library. Put one of them into your hand and the rest into your graveyard. Flashback {6}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Draw two cards, then discard two cards. Untap up to three lands.

Enchant creature card in a graveyard When Animate Dead enters the battlefield, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Animate Dead." Return enchanted creature card to the battlefield under your control and attach Animate Dead to it. When Animate Dead leaves the battlefield, that creature's controller sacrifices it. Enchanted creature gets -1/-0.

Enchant creature card in a graveyard When Dance of the Dead enters the battlefield, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Dance of the Dead." Put enchanted creature card onto the battlefield tapped under your control and attach Dance of the Dead to it. When Dance of the Dead leaves the battlefield, that creature's controller sacrifices it. Enchanted creature gets +1/+1 and doesn't untap during its controller's untap step. At the beginning of the upkeep of enchanted creature's controller, that player may pay {1}{B}. If the player does, untap that creature.

You may cast Necromancy as though it had flash. If you cast it any time a sorcery couldn't have been cast, the controller of the permanent it becomes sacrifices it at the beginning of the next cleanup step. When Necromancy enters the battlefield, if it's on the battlefield, it becomes an Aura with "enchant creature put onto the battlefield with Necromancy." Put target creature card from a graveyard onto the battlefield under your control and attach Necromancy to it. When Necromancy leaves the battlefield, that creature's controller sacrifices it.

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

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

Flying, deathtouch When Baleful Strix enters the battlefield, draw a card.

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.) Draw a card.

Counter target spell.

Deep-Sea Kraken can't be blocked. Suspend 9—{2}{U} (Rather than cast this card from your hand, you may pay {2}{U} and exile it with nine time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.) Whenever an opponent casts a spell, if Deep-Sea Kraken is suspended, remove a time counter from it.

Flash Emerge {5}{U}{U} (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.) When you cast this spell, tap up to four target permanents.

Return to their owners' hands all creatures with toughness less than or equal to the number of Islands you control.

When Mesmerizing Benthid enters the battlefield, create two 0/2 blue Illusion creature tokens with "Whenever this creature blocks a creature, that creature doesn't untap during its controller's next untap step." Mesmerizing Benthid has hexproof as long as you control an Illusion.

Surveil 2, then draw two cards. Notion Rain deals 2 damage to you. (To surveil 2, look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Surveil 3. (Look at the top three cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.) Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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.)

River Serpent can't attack unless there are five or more cards in your graveyard. Cycling {U} ({U}, Discard this card: Draw a card.)

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.) When Sepulchral Primordial enters the battlefield, for each opponent, you may put up to one target creature card from that player's graveyard onto the battlefield under your control.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.) All lands are Islands in addition to their other types. Creatures without flying or islandwalk can't attack.

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Hexproof (This creature can't be the target of spells or abilities your opponents control.) Cycling {U} ({U}, Discard this card: Draw a card.)

Indestructible As long as your devotion to blue is less than five, Thassa isn't a creature. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.) At the beginning of your upkeep, scry 1. {1}{U}: Target creature you control can't be blocked this turn.