Arixmethes, Slumbering Isle enters the battlefield 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}.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

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.)

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.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.) Whenever Colossal Whale attacks, you may exile target creature defending player controls until Colossal Whale leaves the battlefield. (That creature returns under its owner's control.)

Landfall — Whenever a land enters the battlefield under your control, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Whenever a player casts a spell, you may put a +1/+1 counter on Forgotten Ancient. At the beginning of your upkeep, you may move any number of +1/+1 counters from Forgotten Ancient onto other creatures.

Creatures you control with +1/+1 counters on them can't be blocked.

{T}: Add one mana of any type that a land you control could produce. If Incubation Druid has a +1/+1 counter on it, add three mana of that type instead. {3}{G}{G}: Adapt 3. (If this creature has no +1/+1 counters on it, put three +1/+1 counters on it.)

Trample Islandwalk (This creature can't be blocked as long as defending player controls an Island.) Shroud (This creature can't be the target of spells or abilities.)

If one or more +1/+1 counters would be put on a permanent you control, that many plus one +1/+1 counters are put on that permanent instead. {T}: Add X mana of any one color, where X is Kami of Whispered Hopes's power.

{T}: Add {G}.

Each other creature you control enters the battlefield with a number of additional +1/+1 counters on it equal to Master Biomancer's power and as a Mutant in addition to its other types.

When Rishkar, Peema Renegade enters the battlefield, put a +1/+1 counter on each of up to two target creatures. Each creature you control with a counter on it has "{T}: Add {G}."

Islandwalk (This creature can't be blocked as long as defending player controls an Island.) Merfolk spells and Wizard spells you cast cost {1} less to cast.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.) All lands are Islands in addition to their other types. Creatures without flying or islandwalk can't attack.

Islandwalk (This creature can't be blocked as long as defending player controls an Island.) Water Always Wins — Whenever The Flood of Mars attacks, put a flood counter on another target creature or land. If it's a creature, it becomes a copy of The Flood of Mars. If it's a land, it becomes an Island in addition to its other types.

{1}{G}{U}: Put a +1/+1 counter on target creature you control. Whenever one or more +1/+1 counters are put on a creature you control, put that many growth counters on Simic Ascendancy. At the beginning of your upkeep, if Simic Ascendancy has twenty or more growth counters on it, you win the game.

Counter target spell.

Draw a card. You may put a land card from your hand onto the battlefield.

Permanents you control with counters on them gain hexproof and indestructible until end of turn. Prevent all damage that would be dealt to those permanents this turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.