Skyclave Squid

Defender
Landfall — Whenever a land you control enters, Skyclave Squid can attack this turn as though it didn't have defender.

Reef Worm

When Reef Worm dies, create a 3/3 blue Fish creature token with "When this creature dies, create a 6/6 blue Whale creature token with 'When this creature dies, create a 9/9 blue Kraken creature token.'"

Coral Eel

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Early Harvest

Target player untaps all basic lands they control.

Font of Mythos

At the beginning of each player's draw step, that player draws two additional cards.

Druid Class

(Gain the next level as a sorcery to add its ability.)
Landfall — Whenever a land you control enters, you gain 1 life.
{2}{G}: Level 2
You may play an additional land on each of your turns.
{4}{G}: Level 3
When this Class becomes level 3, target land you control becomes a creature with haste and "This creature's power and toughness are each equal to the number of lands you control." It's still a land.

Charge

Creatures you control get +1/+1 until end of turn.

Forced Adaptation

Enchant creature
At the beginning of your upkeep, put a +1/+1 counter on enchanted creature.

Plains

Purple-Crystal Crab

When Purple-Crystal Crab dies, draw a card.

Island

Druid's Deliverance

Prevent all combat damage that would be dealt to you this turn. Populate. (Create a token that's a copy of a creature token you control.)

Forest

Careful Study

Careful Consideration

Target player draws four cards, then discards three cards. If you cast this spell during your main phase, instead that player draws four cards, then discards two cards.

Second Harvest

For each token you control, create a token that's a copy of that permanent.

Hammerhead Shark

Hammerhead Shark can't attack unless defending player controls an Island.

Sol Ring

Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on Chasm Skulker.
When Chasm Skulker dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on Chasm Skulker. (They can't be blocked as long as defending player controls an Island.)