Have

Giant Octopus

Academy Wall

Defender
Whenever you cast an instant or sorcery spell, you may draw a card. If you do, discard a card. This ability triggers only once each turn.

Sage of Days

When this creature enters, look at the top three cards of your library. You may put one of those cards back on top of your library. Put the rest into your graveyard.

Soaring Drake

Thieving Otter

Whenever this creature deals damage to an opponent, draw a card.

Shorecomber Crab

Aegis Turtle

Coral Eel

Daring Thunder-Thief

River Herald Scout

When this creature enters, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Coral Commando

Leapfrog

This creature has flying as long as you've cast an instant or sorcery spell this turn.

Island

Bellowing Crier

When this creature enters, draw a card, then discard a card.

Owl Familiar

Flying
When this creature enters, draw a card, then discard a card.

Caelorna, Coral Tyrant

Tolarian Terror

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

Transit Mage

When this creature enters, you may search your library for an artifact card with mana value 4 or 5, reveal it, put it into your hand, then shuffle.

Storm Crow

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