Marimo-VS-IAS: Our Friends game cover

Marimo-VS-IAS: Our Friends CD Key

Evolve! For our friends is a 3D action game where marimo algae fight for survival as invading sea-dwelling aliens over a lake turned seawater. Train abilities, mow down enemies, and save allies across ~60 missions in Story Mode, with hard modes, upgrades, exploration, and an optional mystery quest.
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Current Lowest Price

19.99$
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Release Date

27 Mar, 2026

Publisher/Developer

JoyPlot

Reviews

Steam: 100.00% positive (1/1)
Metacritic: -

Marimo-VS-IAS: Our Friends Steam Price History Chart

Current Steam price: 19.99$
Lowest Steam price ever: 12.99$ — 2026-10-08
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Marimo-VS-IAS: Our Friends description

Marimo-VS-IAS: Our Friends

Evolve! For our friends――a 3D action game where resilient marimo algae fight to survive against invading alien species in a lake that has become part of the sea. Master a broad range of actions, mow down hostile forces, and strive to safeguard your allies as the story unfolds.

  • Story Mode: A stage-based campaign featuring around 60 missions. Take on tasks that include defeating enemies, sabotaging their operations, and rescuing or defending your friends. Conquer the challenges and then tackle hard-mode versions to aim for the title of ultimate marimo.
  • Marimo Upgrades: Freely customize your marimo’s abilities using items earned from rewards and exploration. Tailor your enhancements to fit each situation, enabling you to overcome powerful foes and high-difficulty missions.
  • Field Exploration: Roam the lake at your own pace to discover hidden items, uncover information, take on side quests, and face lurking dangers. The environment may evolve as the narrative progresses, adding new twists to every journey.
  • Optional Sub-Story: Delve into the mystery behind how the marimo endured drastic environmental changes and how the lake became connected to the sea. Explore the lake to uncover the truth and deepen the world’s lore.

This title shares a world and timeline with the previous game, Marimo-VS-IAS, yet it can be enjoyed completely on its own. The story follows the marimo of Lake Akan, where warming waters and reduced sunlight once threatened their species. With human help, they began to flourish again—until the lake turned seawater, wiping out much of the ecosystem and inviting invading sea life. Mysterious glowing particles appear underwater, driving creatures into frenzy and granting new powers to the remaining marimo.

Dive into a vibrant, evolving underwater world, sharpen your tactics through upgrades, and defend your friends against an escalating threat. Your choices shape the outcome as you explore, fight, and uncover the truth behind this extraordinary convergence of sea and lake.