Flooded Grove

{T}: Add {C}.
{G/U}, {T}: Add {G}{G}, {G}{U}, or {U}{U}.

Merrow Reejerey

Other Merfolk creatures you control get +1/+1.
Whenever you cast a Merfolk spell, you may tap or untap target permanent.

Simic Charm

Choose one —
• Target creature gets +3/+3 until end of turn.
• Permanents you control gain hexproof until end of turn.
• Return target creature to its owner's hand.

Forest

Abundant Growth

Enchant land
When Abundant Growth enters, draw a card.
Enchanted land has "{T}: Add one mana of any color."

Commune with the Gods

Reveal the top five cards of your library. You may put a creature or enchantment card from among them into your hand. Put the rest into your graveyard.

Lingering Mirage

Enchant land
Enchanted land is an Island.
Cycling {2} ({2}, Discard this card: Draw a card.)

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.

Cold-Eyed Selkie

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Cold-Eyed Selkie deals combat damage to a player, you may draw that many cards.

Sylvan Caryatid

Defender, hexproof
{T}: Add one mana of any color.

Spreading Seas

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

Early Frost

Choke

Islands don't untap during their controllers' untap steps.

Lonely Sandbar

Lonely Sandbar enters tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Mana Leak

Counter target spell unless its controller pays {3}.

Arixmethes, Slumbering Isle

Arixmethes, Slumbering Isle enters tapped with five slumber counters on it.
As long as Arixmethes has a slumber counter on it, it's a land. (It's not a creature.)
Whenever you cast a spell, you may remove a slumber counter from Arixmethes.
{T}: Add {G}{U}.

Twiddle

You may tap or untap target artifact, creature, or land.

Sea's Claim

Enchant land (Target a land as you cast this. This card enters attached to that land.)
Enchanted land is an Island.