HIDDEN MOTION · 15 ROUNDS
Track the ball before it disappears, then predict its hidden arrival at the finish line.
Play 15 constant-speed paths with varied speed and cover length. Misses count, then play continues.
READY?
Estimate the ball's constant speed before it vanishes behind the cover.
Keyboard: Space · Touch or mouse: use PREDICT or tap anywhere in the field. No aiming required.
HOW TO PLAY
Watch the pixel ball move toward the patterned hidden zone at a constant speed.
When the ball disappears, mentally continue its motion toward the red finish line.
Press Space or tap PREDICT at the moment you expect the hidden ball to arrive.
OCCLUDED MOTION
The visible approach provides speed information. The hidden section asks you to preserve that speed estimate until the finish.
Speed stays constant within each round, while speed and cover length vary between rounds.
READ YOUR RESULT
Every result compares your prediction with the true arrival time and reports the absolute difference in milliseconds.
This browser game is for entertainment and personal practice, not diagnosis or clinical assessment.
QUESTIONS
No. It continues at the same constant speed established during the visible approach.
Your absolute timing error must fall inside the displayed ± millisecond window.
A longer hidden zone requires maintaining the speed estimate for more time.
The cover becomes longer, speeds vary across a wider range, and the valid timing window narrows.