Rock, Paper, Scissors

Goal

Win as many rounds as possible in a series of 5, 10 or 20 rounds. In each round, you and the AI secretly pick one of the three gestures, then the hands are revealed on the third beat: “Rock… paper… scissors!”

What beats what

• Rock breaks scissors.
• Paper wraps rock.
• Scissors cut paper.
• Two identical gestures: a tie, the round scores nothing.

At the end of the series, the player who won the most rounds wins. If the rounds won are equal, the series is a draw.

Controls

• Tap a gesture, or use the 1, 2, 3 keys (or R, P, C).
• The “Prediction” panel shows, after each round, what the AI thought you would play.
• The “Your tendencies” panel reveals your reflexes: these are what the AI exploits.

About the AI

The AI runs about fifteen predictors: overall and recent frequencies, order 1 to 3 Markov chains on your gestures and on pairs of gestures, reactions to the previous result (win-stay, lose-shift), cycle detection, a counter to the AI’s own last move, and a search for the longest pattern already seen in the history. Each prediction comes in three meta-strategies (the “Sicilian reasoning” of Iocaine Powder: what if you anticipated its prediction?), and a second family assumes that you are trying to predict the AI yourself. All these strategies are scored on their recent gains over several memory horizons, and the best one is kept with a statistical safety margin.

At Master level, if no reliable pattern is detected, the AI plays perfectly at random: it then becomes unexploitable. The AI keeps your last 300 gestures in memory from one game to the next (erasable in the side panel). It never sees your choice: its gesture is sealed before yours.