The Lost Code of Janken
The untold origin story of the world's most dangerous game
The Secret Tool
Rumour has it that in the neon-lit chaos of the 1980s, oppressed developers at one of Japan's most formidable game studios created a secret tool to overthrow their tyranical boss — a disguised training program for strategic thought and psychological warfare.
What looked like a harmless office game was, in truth, a mind-manipulation simulator — a framework designed to identify the sharpest tactical thinkers.
The Boss
An individual so feared, so ruthless, that he immortalised himself as one of gaming's most notorious villains.
Whispers persist that this unnamed figure still lingers in a dimly lit alleyway somewhere in Osaka — a mythical presence never spoken aloud.
The Purge
When The Boss discovered the experiment, they ordered every floppy disk and cartridge destroyed.
All were wiped… except one.
The surviving source code was hidden away — protected at all costs and passed through underground networks for decades.
The Recovery
Decades later, that surviving code was recovered.
Engineers, historians, and rogue psychologists joined forces to rebuild it — remastering the lost framework to create the largest Rock Paper Scissors competition the world has ever seen.
The Janken Pro League
Thus was born the Janken Pro League, powered by S.A.D.I. — the first system capable of simulating the chaos and consciousness of live competition.
What began as a tool for revolution has evolved into something far greater — a global proving ground where the greatest tactical minds clash.
So step into the arena.
Face your rivals. Test your instinct.
And see whether you're destined to be fortunate — or merely forgotten.
Enter the Arena