Reflections of Littjara

As Reflections of Littjara enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Engulf the Shore

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

Obelisk of Urd

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
As Obelisk of Urd enters the battlefield, choose a creature type.
Creatures you control of the chosen type get +2/+2.

Hard Evidence

Create a 0/3 blue Crab creature token.
Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Leap

Target creature gains flying until end of turn.
Draw a card.

Path of Ancestry

Path of Ancestry enters the battlefield 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.)

Thermal Flux

Choose one —
• Target nonsnow permanent becomes snow until end of turn.
• Target snow permanent isn't snow until end of turn.
Draw a card at the beginning of the next turn's upkeep.

Breaching Hippocamp

Flash (You may cast this spell any time you could cast an instant.)
When Breaching Hippocamp enters the battlefield, untap another target creature you control.

Adaptive Automaton

As Adaptive Automaton enters the battlefield, choose a creature type.
Adaptive Automaton is the chosen type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

Jace's Mindseeker

Flying
When Jace's Mindseeker enters the battlefield, target opponent mills five cards. You may cast an instant or sorcery spell from among them without paying its mana cost.

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Commander's Sphere

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

Trait Doctoring

Change the text of target permanent by replacing all instances of one color word with another or one basic land type with another until end of turn.
Cipher (Then you may exile this spell card encoded on a creature you control. Whenever that creature deals combat damage to a player, its controller may cast a copy of the encoded card without paying its mana cost.)

Sol Ring

Surge Mare

Surge Mare can't be blocked by green creatures.
Whenever Surge Mare deals damage to an opponent, you may draw a card. If you do, discard a card.
{1}{U}: Surge Mare gets +2/-2 until end of turn.

Ancient Carp

Counterspell

Arcane Signet

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

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Coral Eel

Cloud Manta

Slipstream Eel

Slipstream Eel can't attack unless defending player controls an Island.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)

Energy Tap

Tap target untapped creature you control. If you do, add an amount of {C} equal to that creature's mana value.

Sky Diamond

Sky Diamond enters the battlefield tapped.
{T}: Add {U}.

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters the battlefield tapped unless you control three or more other Islands.
When Mystic Sanctuary enters the battlefield untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Wavebreak Hippocamp

Whenever you cast your first spell during each opponent's turn, draw a card.

Mind Bend

Change the text of target permanent by replacing all instances of one color word with another or one basic land type with another. (For example, you may change "nonblack creature" to "nongreen creature" or "forestwalk" to "islandwalk." This effect lasts indefinitely.)

Mystic Remora

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays {4}.

Cloudpost

Cloudpost enters the battlefield tapped.
{T}: Add {C} for each Locus on the battlefield.

Dream's Grip

Choose one —
• Tap target permanent.
• Untap target permanent.
Entwine {1} (Choose both if you pay the entwine cost.)

Twitch

You may tap or untap target artifact, creature, or land.
Draw a card.

Vanquisher's Banner

As Vanquisher's Banner enters the battlefield, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Skyswimmer Koi

Flying
Whenever an artifact enters the battlefield under your control, you may draw a card. If you do, discard a card.

Gilded Lotus

Orvar, the All-Form

Changeling
Whenever you cast an instant or sorcery spell, if it targets one or more other permanents you control, create a token that's a copy of one of those permanents.
When a spell or ability an opponent controls causes you to discard this card, create a token that's a copy of target permanent.

Herald's Horn

As Herald's Horn enters the battlefield, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Tidal Barracuda

Any player may cast spells as though they had flash.
Your opponents can't cast spells during your turn.

Fleet Swallower

Whenever Fleet Swallower attacks, target player mills half their library, rounded up.

Grisly Anglerfish

{6}: Creatures your opponents control attack this turn if able.

Grizzled Angler

{T}: Mill two cards. Then if there is a colorless creature card in your graveyard, transform Grizzled Angler.

Grizzled Angler // Grisly Anglerfish

Dandân

Dandân can't attack unless defending player controls an Island.
When you control no Islands, sacrifice Dandân.

High Tide

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

Fleeting Distraction

Target creature gets -1/-0 until end of turn.
Draw a card.

Otawara, Soaring City

{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.

Twisted Image

Switch target creature's power and toughness until end of turn.
Draw a card.

Enervate

Tap target artifact, creature, or land.
Draw a card at the beginning of the next turn's upkeep.

Teferi's Time Twist

Exile target permanent you control. Return that card to the battlefield under its owner's control at the beginning of the next end step. If it enters the battlefield as a creature, it enters with an additional +1/+1 counter on it.

Whim of Volrath

Buyback {2} (You may pay an additional {2} as you cast this spell. If you do, put this card into your hand as it resolves.)
Change the text of target permanent by replacing all instances of one color word with another or one basic land type with another until end of turn. (For example, you may change "nonred creature" to "nongreen creature" or "plainswalk" to "swampwalk.")

Vivid Flying Fish

Vivid Flying Fish has flying as long as it's attacking. (It can't be blocked except by creatures with flying or reach.)

Moonlace

Target spell or permanent becomes colorless.

Stinging Lionfish

Whenever you cast your first spell during each opponent's turn, you may tap or untap target nonland permanent.

Island

Whelming Wave

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

Aquitect's Will

Put a flood counter on target land. That land is an Island in addition to its other types for as long as it has a flood counter on it. If you control a Merfolk, draw a card.

Mind Games

Buyback {2}{U} (You may pay an additional {2}{U} as you cast this spell. If you do, put this card into your hand as it resolves.)
Tap target artifact, creature, or land.

Kapsho Kitefins

Flying
Whenever Kapsho Kitefins or another creature enters the battlefield under your control, tap target creature an opponent controls.

Shadow Rift

Target creature gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)
Draw a card.

Gigadrowse

Replicate {U} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Tap target permanent.

Mana Drain

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

Deepglow Skate

When Deepglow Skate enters the battlefield, double the number of each kind of counter on any number of target permanents.

Devouring Deep

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Hall of Storm Giants

If you control two or more other lands, Hall of Storm Giants enters the battlefield tapped.
{T}: Add {U}.
{5}{U}: Until end of turn, Hall of Storm Giants becomes a 7/7 blue Giant creature with ward {3}. It's still a land. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Sky-Eel School

Flying
When Sky-Eel School enters the battlefield, draw a card, then discard a card.

Windrider Eel

Flying
Landfall — Whenever a land enters the battlefield under your control, Windrider Eel gets +2/+2 until end of turn.

Kindred Discovery

As Kindred Discovery enters the battlefield, choose a creature type.
Whenever a creature you control of the chosen type enters the battlefield or attacks, draw a card.

Skitter Eel

{2}{U}: Adapt 2. (If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.)

Exchange of Words

When Exchange of Words enters the battlefield, choose two target creatures. For as long as Exchange of Words remains on the battlefield, exchange the text boxes of those creatures.

Mystic Skyfish

Whenever you draw your second card each turn, Mystic Skyfish gains flying until end of turn.

Aboleth Spawn

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

School of Piranha

At the beginning of your upkeep, sacrifice School of Piranha unless you pay {1}{U}.

Kiora Bests the Sea God

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Create an 8/8 blue Kraken creature token with hexproof.
II — Tap all nonland permanents target opponent controls. They don't untap during their controller's next untap step.
III — Gain control of target permanent an opponent controls. Untap it.

Quest for Ula's Temple

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.