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.)

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

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.

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.)

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

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

{2}, {T}: Add {B} for each Swamp you control.

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}.

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

{T}: Add one mana of any color.

{T}: Add {U}.

{T}: Add {B}.

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

Flying

Whenever an opponent draws a card, you may draw two cards.

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.")

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

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, 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.

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

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}.

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

Return target creature card from your graveyard to the battlefield.

Flashback--Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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

{T}, Sacrifice Fabled Passage: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

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.

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

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

Fetid Pools enters the battlefield tapped.

Cycling {2} ({2}, Discard this card: Draw a card.)

Return all nonland permanents to their owners' hands. If you return four or more nontoken permanents you control this way, you may put a permanent card from your hand onto the battlefield.

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.

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

Creatures you control get -1/-1.

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.

Equip {5}

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.

Demonstrate (When you cast this spell, you may copy it. If you do, choose an opponent to also copy it.)

Mill five cards, then return a creature card from your graveyard to the battlefield.

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.

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

Equip {0}

Each player exiles all creature cards from their graveyard, then sacrifices all creatures they control, then puts all cards they exiled this way onto the battlefield.

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.

Whenever Lorthos, the Tidemaker attacks, you may pay {8}. If you do, tap up to eight target permanents. Those permanents don't untap during their controllers' next untap steps.

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.

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}: Draw a card, then discard a card.

{2}{U}{B}, {T}, Sacrifice Obsessive Stitcher: Return target creature card from your graveyard to the battlefield.

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.)

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.

Exploit (When this creature enters the battlefield, you may sacrifice a creature.)

When Rot-Tide Gargantua exploits a creature, each opponent sacrifices a creature.

Flying

When Runo Stromkirk enters the battlefield, put up to one target creature card from your graveyard on top of your library.

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If a creature card with mana value 6 or greater is revealed this way, transform Runo Stromkirk.

Flying

Whenever Krothuss, Lord of the Deep attacks, create a tapped and attacking token that's a copy of another target attacking creature. If that creature is a Kraken, Leviathan, Octopus, or Serpent, create two of those tokens instead.

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 Sakashima the Impostor enter the battlefield as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return this creature to its owner's hand at the beginning of the next end step."

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.

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.

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

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, Shadow Kin becomes a copy of that card, except it has this ability.

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.

At the beginning of each opponent's upkeep, that player sacrifices a creature.

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

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

Kicker {3}

Indestructible

When Skyclave Relic enters the battlefield, if it was kicked, create two tapped tokens that are copies of Skyclave Relic.

{T}: Add one mana of any color.

Kicker {1}{U} (You may pay an additional {1}{U} as you cast this spell.)

When Slinn Voda, the Rising Deep enters the battlefield, if it was kicked, return all creatures to their owners' hands except for Merfolk, Krakens, Leviathans, Octopuses, and Serpents.

({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}.)

({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 {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.

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

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."

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.

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Cycling {U} ({U}, Discard this card: Draw a card.)

({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}.

Equipped creature gets +2/+2 and has protection from green and from white.

Whenever equipped creature deals combat damage to a player, exile up to one target creature you own, then search your library for a basic land card. Put both cards onto the battlefield under your control, then shuffle.

Equip {2}

{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.

Temple of Deceit enters the battlefield tapped.

When Temple of Deceit enters the battlefield, scry 1.

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

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.

This spell costs {2} less to cast for each creature card in your graveyard.

Whenever a creature you control dies, put it on the bottom of its owner's library.

{2}{B}, {T}, Pay 2 life: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.

Tromokratis has hexproof unless it's attacking or blocking.

Tromokratis can't be blocked unless all creatures defending player controls block it. (If any creature that player controls doesn't block this creature, it can't be blocked.)

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

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

You may cast spells as though they had flash.

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

As Watery Grave enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Return all creatures to their owners' hands except for Krakens, Leviathans, Octopuses, and Serpents.

Creatures you control have lifelink.

{2}{B}{B}, {T}: Return target creature card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step. If it would leave the battlefield, exile it instead of putting it anywhere else. Activate only as a sorcery.

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Flying

As long as Wonder is in your graveyard and you control an Island, creatures you control have flying.

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.