Rock Paper Scissors

The classic schoolyard game with a crypto.getRandomValues opponent — the computer's pick is uniformly random and chosen at the same moment yours is, so there's no peeking. Streak counter goes positive for wins, negative for losses, and tracks your best run. Match mode caps the game at best-of-3, 5 or 10 with a winner banner when one side hits the target. Useful when a coin flip won't do because three people need a way to break a tie.

A uniformly random opponent is unbeatable in the only sense that matters: against it every strategy has the same expected result, a third wins, a third losses, a third draws. No pattern you play can do better, and none can do worse either, which makes this version a fair coin with three faces rather than a game of skill.

That is precisely what the game is not between people. Human play is famously exploitable: players throw rock more often than a third of the time, especially when losing, and tend to switch after a loss and repeat after a win. Competitive play is entirely about reading those habits, which is why a tournament has world champions and a random opponent cannot be one. If you want the game to be a contest, you need a human on the other side.

Draws are a real outcome rather than a failure, and they happen a third of the time. For a best-of series that matters: a best-of-3 takes on average closer to four or five rounds than three, because roughly one round in three decides nothing.

The streak counter is where the illusion lives. A run of five wins against a uniform opponent happens about once in every 243 attempts at that point in a sequence, which is often enough that it will happen to you and will feel like something. It is not evidence of a pattern; the next round is still one in three.