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YOU / YUTAKUROURUSHI / FLY BRAIN
MOVE + ATTACK TOGETHERWASD MOVE · J ATTACK · K HEAVY · I RIKA · L BLOCK
MOVE / JUMP
FIGHT

Hold a direction. Tap an attack. Hold Block to defend.

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Leaderboard

Win two rounds. Fastest time wins; health breaks ties.

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Shared results reported by each player's browser.

HOW TO PLAY

Move and jump with the left pad. Use Attack for quick punches, Heavy for committed hits, and hold Block to defend. Rika Assist charges over time and with clean hits. When ready, tap Rika for a powerful close-range swipe. Kurourushi sends a Roach Swarm across the ground—hold Block or jump clear. Both powers have a short windup and a six-second cooldown. Crouch with the down arrow.

Win two rounds to take the match. The game handles spacing, hit reactions, recovery and knockdowns. Attacks need a new tap; holding Block keeps your guard up.

Keyboard: A/D move, W jump, S crouch. J quick attack, K heavy attack, I Rika, L block. Space pauses.

WHAT THE FLY SEES
Exact simplified opponent image sent to the fly

No decision recorded yet.

The circuit receives a simplified opponent-only image. The thumbnail shows the exact input used for each recorded decision. It contains no HUD, future button presses or health values.

TRIVIA · THE BRAIN’S TWO SIDES

A dark side can still be firing. With Changes on, the map highlights only neurons whose spike counts changed since the previous decision. Our visual input sends different parts of the image to the left and right eye pathways. When Yuta stays on one side, changes can cluster there while both sides keep firing.

Turn Changes off to see total recorded activity. Brain 3D shows neurons with known locations; All cells also includes those without coordinates. This pattern describes our simulation and its experimental camera mapping.

ABOUT & CREDITS

Play Yuta against Kurourushi, controlled by a frozen MaleCNS fly circuit. This fan-made encounter adapts the Sendai setting: Rika Assist and Roach Swarm are game mechanics, not a shot-for-shot reconstruction of the anime.

Built on Hackfighter by quarker1337 and contributors, with adapted combat, original generated character artwork and scenery, a neural controller and mobile controls. Jujutsu Kaisen characters belong to their respective creators. Yuta / Rika reference.

Hackfighter code: MIT. Creative assets: CC BY 4.0. Asset notice. All credits & licenses. The neural simulation uses the pinned Stonkfly backend. The circuit is frozen. Each opponent-only image runs through a fresh 100 ms neural window; a trained external readout converts the resulting neural spike counts into game inputs. That readout was trained for this camera; the connectome itself did not learn these moves. The simplified cue camera is an engineered interface, not biological fly eyesight.

The game runs at its native pace. A neural choice is briefly held while the next image is processed; failed or old responses cannot activate the built-in CPU. Leaderboard results are tied to a neural session and reported by the browser; they are separate from the server-verified simulation scores.