Island

Plains

Tuvasa the Sunlit

Tuvasa gets +1/+1 for each enchantment you control.
Whenever you cast your first enchantment spell each turn, draw a card.

Deeproot Waters

Whenever you cast a Merfolk spell, create a 1/1 blue Merfolk creature token with hexproof. (A creature with hexproof can't be the target of spells or abilities your opponents control.)

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Merrow Commerce

At the beginning of your end step, untap all Merfolk you control.