
Koi Katana
Serene lakes. Sudden blades.
Fish the koi lake, cut through the Crimson Thicket, and calm the spirit beneath the water. A low-poly fishing and sword game that plays in your phone or desktop browser, alone or with up to three friends.
Nothing to install. Your saves stay in your browser.
“Where did you come from? Inside with you.”
Sixteen today
You were six when Genzo and Hana found you after the storm, and they took you in. They kept the day they found you as your birthday.
Ten years on, Hana gives you a book. Genzo gives you a sword nobody can name. It stings every time you swing it, and nobody in Koi Landing knows why.

Past the bramble gate, the lanterns are red
Carry any sword and the bramble gate opens onto the Crimson Thicket, where the Fox Lord's hunters wait. Lock on, chain light cuts, charge a heavy, guard, and dodge through a strike. On a phone that's four buttons and a stick; on a keyboard, J, K, L and Space.
Moss Spirit
Whispering Forest
A lumbering golem of soured moss. Step out of the circle before the slam.
Kitsune Hunter
Crimson Thicket
A fast, masked spearman. The lunge comes down a straight line.
Kappa
Koi Lake
A river brawler in a turtle shell, hauled out of the water on a rare bite.
Stillwater Spirit
Koi Lake
The lake's guardian, grown restless. Beat it for an enchantment.
The Fox Lord
His hall in the Crimson Thicket
Nine foxfire tails and a burning blade. He blinks to your side, and below half health the foxfire falls four at once.
Five blades on the rack
Each sword at Takeda's dojo carries one element. The element decides when its Tick opens, the moment its power breaks loose, and what it leaves on the enemy. The elements turn on a wheel, each beating the next, so the blade you carry decides which fights go your way.
Reflection
Water blade, natural persona Mindfulness
Adaptation and redirection. Turn their strength back on them.
Mastered by the God Swordsman Shizuka.
- Its Tick opens
- After a perfect guard
- Leaves behind
- Soak, which slows and conducts lightning
- Strong against
- Fire: water douses it
- Weak to
- Lightning, which conducts through it
Fish are the money here
Sell the catch at Genzo's stall, or carry it up to Aya's forge in Koi Landing. Each of them pays their own price for each species, so a fish one shrugs at, the other might want.
Cook what you keep into a meal buff, buy bait, and have Aya reforge your blade. Then take the harder road. Farm easy fish slowly, or risk the rare ones.
Koi Landing
Take a sword from Takeda's dojo
Whispering Forest
Cut through the moss spirits
Koi Lake
Cast, hook, and reel
Home again
Sell, cook, and reforge
Crimson Thicket
Go deeper, where it pays more


A quiet cast
Cast and watch the float. A koi comes in to look, nibbles, then takes it. Hook on the dip, then fight it: hold the side away from its run, and keep the line tight without snapping it.

Cast anywhere on the water. Casts into the rings get a quicker bite, and the shy fish come to them.
Your creel 0 of 6 species
- Reed Minnow
- Pond Koi
- Silver Carp
- Moon Koi
- Myth Koi
- Ryūjin Koi
Up to four on the water
Open a party and share its code. Friends drop into your world from their own browsers, and the room server runs the fight, so everyone faces the same Kappa.
Stand together and you can duel: a friendly bout, unranked, that nobody dies of.
