REACT OR FREEZE · 20 ROUNDS
Respond fast on green. Stay completely still on red until it is safe.
Complete 20 balanced rounds. Mistakes count and the game continues.
READY?
Keyboard: press Space or Enter. Mobile: tap the large response button.
Press Space or Enter, or tap the button, only while the light is green.
HOW TO PLAY
Start the game and wait for the light after each short pause.
On green, immediately press Space or Enter, or tap the large response button.
On red, do nothing until SAFE appears. In standard mode, all 20 rounds count.
REACTION + RESTRAINT
You alternate between a quick physical response and deliberate restraint. Green lights test simple reaction speed, while red lights test whether you can stop an expected action.
The large symbols and written instructions accompany color, so the rule remains clear without relying on color alone.
READ YOUR RESULT
Accuracy includes correct green responses and correctly held red lights. Average reaction time uses correct green responses only.
For a fair personal comparison, use the same device and input method each time. Display and input latency can affect results.
QUESTIONS
Exactly 20: 10 green lights and 10 red lights in a shuffled order. Every round advances, even after a mistake.
Use either Space or Enter when the light is green. On a phone or tablet, tap the large response button.
A red light is correct when you make no response for the complete hold window. SAFE confirms that the round is over.
The first missed green light or response to red ends the run. Each correct round makes the next response window a little shorter.