Game review by
Chad Sapieha, Common Sense Media
Koi Game Poster Image
Cute but shallow fish tale with eco message makes no waves.

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A lot or a little?

The parents' guide to what's in this game.

Educational Value

Kids can learn about the effects of pollution on animals and the environment, as well as do a bit of memory training in this simple all-ages puzzle adventure. The story focuses on the consequences of pollution in natural environments by depicting the effects of toxins on animals and their habitats. Kids will see fish behaving in ways they normally wouldn't and watch as they're forced to swim through mazes of man-made debris. Pop-up puzzles, meanwhile, will challenge players to memorize and match colorful patterns on the backs of lizards and the sequences of sounds played on the leaves of branches. The challenge level is a little uneven, though, so younger kids may go from being pleasantly entertained to suddenly frustrated. Koi is unlikely to prove revelatory even to its youngest players, but it could get kids thinking a bit more about the world around them.

Positive Messages

Attempts to depict effects of human pollution on lives, world of aquatic creatures.

Positive Role Models & Representations

Player's fish engages in kind, friendly activities as it swims about helping, guiding other fish, occasionally causing flowers to bloom.

Ease of Play

Straightforward controls, no way to lose, but some memory, tile puzzles could be a bit tricky for younger players.

Violence & Scariness

Small fish can be stunned by bigger fish if they bump into them. They can also be shocked by broken wires, with an animation that shows flashes of their skeletons. They're never killed, seriously injured.


What parents need to know

Parents need to know that Koi is a downloadable aquatic adventure without any real violence. The worst players see is fish getting stunned by bumping into bigger fish or shocked if they swim too close to exposed electrical wires. Since the cast is composed only of frolicking fish and frogs, there's not really any opportunity for racy content. But the story does carry a somber message about pollution and the impact it can have on aquatic creatures and environments. Parents should also note that while the controls are simple, younger children may have a tough time with some of the game's puzzles, which include memory challenges and maze-like level designs that require a pretty good sense of direction.

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What's it about?

KOI puts players in control of a wee fish swimming about ponds, rivers, and man-made waterways, including drains and sewers. Your fish will meet other fish and frogs in a simple story that explores how pollution is affecting the environment and the behaviors of aquatic animals. Each short level is distinguished by its objectives and puzzles. Players generally need to track down other fish and lead them to floating flowers to help them bloom. But along the way they'll run into dark and angry fish that try to bump into them, exposed wires that can shock them, and swift currents they'll either zip through or struggle against. Some levels force players to complete simple challenges that involve remembering audiovisual sequences, spinning mosaic tiles, and finding their way through darkened sewer mazes. Players also need to keep an eye out for jigsaw puzzle pieces and stars hidden around the watery world that must be collected to achieve a perfect rating on each level.

Is it any good?

This ecological adventure has grand aspirations it never quite manages to achieve. It's clearly aiming to be a beautiful and relaxing game with a serious message and was likely at least partially inspired by ThatGameCompany's poetic Flower. But while Koi successfully achieves a calming atmosphere, it doesn't manage the subtly sophisticated aesthetic, play mechanics, or meaning of its muse.

Early stages set in natural environments have an appealing minimalist appearance, but man-made objects introduced in later stages -- boots, pipes, and gears -- have a decidedly underwhelming cardboard-cutout look that feels a bit cheap. And while swimming around can be fun and even soothing, the puzzles are poorly integrated and a bit jarring when they suddenly lift players out of the pond to begin picking leaves on a branch or spinning mosaic squares. Most problematic, though, is that the message -- pollution is bad for animals -- is simultaneously too blunt and too simplistic. Yes, pollution is bad, but how can we address it? What's the root problem? These ideas are never addressed, leaving players to either feel sorry for the fish or take some solace in the game's rather fantastical conclusion. A more symbolic expression of the same themes would have served Koi better.

Talk to your kids about ...

  • Families can talk about screen time. This is a short game with only a handful of levels, all of which can be completed in a couple of hours. So, with a game this brief, do you think it's better to finish it all in one go, or should players break it up into a few small chunks? Why?

  • Talk about pollution. While we're pretty good at ensuring our own environments stay clean and safe, sometimes human activities can have disastrous effects on the animal world, so what can you do to minimize your impact on the ecosystem around you?

Game details

Our editors recommend

For kids who love environmentalism

Themes & Topics

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