Ponder

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

Crown of Ascension

Enchant creature
Enchanted creature has flying.
Sacrifice Crown of Ascension: Enchanted creature and other creatures that share a creature type with it gain flying until end of turn.

Claustrophobia

Enchant creature
When Claustrophobia enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Stonybrook Banneret

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Merfolk spells and Wizard spells you cast cost {1} less to cast.

Counterspell

Unwind

Counter target noncreature spell. Untap up to three lands.

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.

Inkfathom Divers

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
When Inkfathom Divers enters, look at the top four cards of your library, then put them back in any order.

Merfolk Looter

Blue Elemental Blast

Choose one —
• Counter target red spell.
• Destroy target red permanent.

Volshe Tideturner

{T}: Add {U}. Spend this mana only to cast an instant or sorcery spell or a kicked spell.

Stonybrook Angler

{1}{U}, {T}: You may tap or untap target creature.

Spreading Seas

Enchant land
When Spreading Seas enters, draw a card.
Enchanted land is an Island.

Unsummon

Return target creature to its owner's hand.

Helm of the Ghastlord

Enchant creature
As long as enchanted creature is blue, it gets +1/+1 and has "Whenever this creature deals damage to an opponent, draw a card."
As long as enchanted creature is black, it gets +1/+1 and has "Whenever this creature deals damage to an opponent, that player discards a card."

Island

Library Larcenist

Whenever Library Larcenist attacks, draw a card.

Streambed Aquitects

{T}: Target Merfolk creature gets +1/+1 and gains islandwalk until end of turn. (It can't be blocked as long as defending player controls an Island.)
{T}: Target land becomes an Island until end of turn.