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Oskar's hysteresis mazes

This puzzle is based on an original mechanical puzzle by Oskar van Deventer. Your challenge is to manouvre the black ball to the red square using east/west movement only. You rely on the sloping walls to push the ball north/south.

Later mazes include special yellow switch points where you can choose between east/west movement or north/south movement. Your choice will stay in force until you reach another switch point.

Sorry, this is a Java applet.


Click Restart to load first maze or reload current maze.
Click Previous/Next to switch between mazes.


Use the cursor keys to shift the ball.


n - next maze
p - previous maze
r - restart current maze

The photo on the right shows the original Hysteresis Key puzzle designed by Oskar. Here the red key and blue 'rocker' interact to create the maze. Thanks to careful design of the maze the key slides easily into the lock but removing it again is quite a different matter

concept & mechanical puzzle - © Oskar van Deventer 2000
applet & maze designs - © Andrea Gilbert 2000
applet JS conversion - cheerpj transpiler from Leaning Technologies - 2020