Benthic Giant

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

Call to Heel

Return target creature to its owner's hand. Its controller draws a card.

Claustrophobia

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

Coralhelm Guide

{4}{U}: Target creature can't be blocked this turn.

Fog Bank

Defender (This creature can't attack.)
Flying
Prevent all combat damage that would be dealt to and dealt by this creature.

Frost Lynx

When this creature enters, tap target creature an opponent controls. That creature doesn't untap during its controller's next untap step.

Impulse

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Toothy, Imaginary Friend

Pir, Imaginative Rascal

Partner with Pir, Imaginative Rascal (When this creature enters, target player may put Pir into their hand from their library, then shuffle.)
Whenever you draw a card, put a +1/+1 counter on Toothy.
When Toothy leaves the battlefield, draw a card for each +1/+1 counter on it.

Kitesail Corsair

This creature has flying as long as it's attacking.

Kraken Hatchling

Kiora, the Tide's Fury

Mystic Confluence

Choose three. You may choose the same mode more than once.
• Counter target spell unless its controller pays {3}.
• Return target creature to its owner's hand.
• Draw a card.

Negate

Nimbus of the Isles

Flying (This creature can't be blocked except by creatures with flying or reach.)

Omenspeaker

When this creature enters, 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.)

Opportunity

Oracle's Insight

Enchant creature
Enchanted creature has "{T}: Scry 1, then draw a card." (To scry 1, look at the top card of your library, then you may put that card on the bottom.)

Battlebond