How do you play Rock Paper Scissors here?
Pick a mode on the title screen, then tap one of the three buttons at the bottom. Both hands pump three times to the "Rock, Paper, Scissors!" chant and open at the same moment. Rock beats scissors, scissors beats paper, paper beats rock.
Every hand is drawn as a coloured glove, so rock, paper and scissors are easy to tell apart. The winning hand grows and sends out a golden ring, the losing hand shakes and fades, and once a streak passes 3 the counter catches fire. There are six modes in all: Win Streak, Muk-jji-ppa, Muk-jji-ppa for two, Speed Round, Tournament and Two Players, and each starts right away on the same screen.
Does the computer really read your hand?
Yes. Normal looks at your last 10 throws, guesses the one you use most and plays the hand that beats it. Hard uses a second order Markov model: it records what you threw after each pair of hands and predicts the next one. Easy is pure random.
| Level | How it chooses | How to beat it |
|---|---|---|
| Easy | All three hands equally likely | Luck. You win about one round in three |
| Normal | Counters your most common hand of the last 10. 35% random | Change the hand you favour |
| Hard | Predicts from the last two hands you threw. Only 12% random | Never repeat the same sequence twice |
The Hard rival also talks before you choose: "Rock this time?" or "You like Rock, huh?". When one hand makes up more than 45% of your recent throws it names that hand, so the speech bubble is a mirror of your own habit. People tend to avoid throwing the same hand three times and to copy the hand that just beat them, and that is exactly the kind of pattern a Markov model picks up.
What are the Muk-jji-ppa rules?
First play normal rock paper scissors to decide who attacks. From then on, whenever both players throw the same hand, the attacker scores a point. If the hands differ, the winner of that throw takes over as attacker.
- Play rock paper scissors. The winner gets the "Attack" badge; a draw is replayed.
- In the attack phase the hands are called Muk (rock), Jji (scissors) and Ppa (paper) in Korean.
- A matching throw gives the attacker one point and the round restarts from rock paper scissors.
- A different throw hands the attack to whoever won it, and the next throw follows at once.
- First to 3 points wins.
When the computer attacks it throws the hand it expects from you; when it defends it throws the hand that beats that. On Hard, holding the attack and repeating a hand twice is the quickest way to give away a point.
How is the Speed Round scored?
For 30 seconds a rival hand drops into the middle of the screen and you tap the hand that beats it as fast as you can. A correct tap counts one point; a wrong tap takes 2 seconds off the clock.
After five correct answers a red banner reading "LOSING hand!" starts to appear now and then. While it shows, the right answer is the hand that loses to the one on screen. Switching between the green and red banners is where most mistakes happen. Every 10 answers in a row sets off fireworks, and the result card shows your total, your best combo and your misses.
How are the 8 tournament rivals different?
Each rival chooses hands in its own way, and you play best of 3 against each one to move up. Draws are replayed. Two losses to any rival knock you out on the spot.
| # | Rival | Habit |
|---|---|---|
| 1 | Rocky | Rock two times out of three |
| 2 | Snippy | Loves scissors, otherwise beats your last hand |
| 3 | Echo | Assumes you will repeat and beats your last hand |
| 4 | Copycat | Copies your last hand |
| 5 | Fickle | Never throws the same hand twice in a row |
| 6 | Contrary | Expects you to beat its last hand and goes one step further |
| 7 | Mind Reader | Frequency analysis, like the Normal computer |
| 8 | Champ | Markov prediction like the Hard computer, plus mind games |
Each rival drops a hint about its habit in the first round: "Rock is king", "Me too!" and so on. Trust the hint and the first six can be beaten almost every time. Against Copycat, throw the hand that beats what you just threw; against Contrary, throw the hand that loses to its last hand.
How does two player mode work?
The screen splits in half, each player taps their own buttons, and both hands open together when the 3 second countdown ends. Your choice stays hidden; only a "Ready" badge shows.
- In landscape the halves are left and right; on a phone in portrait they are top and bottom, and the top half is turned upside down so the player sitting opposite can read it.
- If a player has not chosen when the countdown ends, a random hand is thrown for them. You can change your pick during the countdown.
- Two Players ends at 5 points, Muk-jji-ppa for two at 3 points.
- Keyboard: left (bottom) player A S D or 1 2 3, right (top) player J K L or the arrow keys.
Tips for beating the computer
- Drop your favourite hand. Normal and Hard target the hand you throw most. Mixing all three evenly brings your odds back to about one in three.
- Break the sequence on Hard. When your last two hands match an earlier pair, throw something different from what followed last time and the prediction misses.
- Read the bubble backwards. "You like Rock, huh?" means the computer is readying paper, so scissors is the play.
- Keep the same hand while attacking in Muk-jji-ppa. The harder the rival tries to match you, the more likely a match, and a match is your point.
- Look at the banner colour first in Speed Round. Green or red before the hand shape cuts your misses.
Controls
- Touch or mouse: tap or click one of the three glove buttons at the bottom. In two player mode each player uses the buttons on their own half.
- Keyboard: 1 2 3 or A S D follow the button order (Rock, Paper, Scissors). The right (top) player in two player mode uses J K L or the left, down and right arrows. Enter or Space on the title screen starts the last mode you played.
- Buttons: 🔊 at the top right toggles sound, ⌂ returns to the title screen.
Best results for Win Streak, Speed Round and Tournament and the sound setting are stored only in this browser and never sent to a server. The chant and every sound effect are synthesised in code, so nothing is downloaded.