How to play Escher's Impossible Waterfall.
This is common square rotating puzzle. Click on the puzzle pieces while they fit the original picture. Use the "hint" button for help.
Know a famous image with impossible optical illusion.
Winning the game rewards +1 Knowledge Level
The download version(bottom of the page) include an executable file for Windows OS with local levels only.
Here is a gameplay movie of psychology square puzzles on YouTube.