Object: Collect all white tokens. 
 
Click the board to drop a random set of 40 walls. Then drop the two Twins (orange and black ball). The Orange Twin is the guide and the Black Twin follows.
 
You move the Orange Ball one step into any direction. The Black Ball then follows the Orange Ball like a Siamese twin, always keeping the same distance (the sum of horizontal and vertical distance is always four units).
 
Only the Black Twin can capture the white Tokens, however. You win if you have collected all the white tokens.
 
In the default variant the Black Twin chooses randomly from the moves available.
Variant 2 gives the following move-priorities to the Black Twin: North, South, East, West, NorthE, NorthW, SouthE, SouthW.
 
 
The Monster Maze by Robert A. Kraus reminded me of a mechanical puzzle I invented many years ago. My puzzle had no chasing element, though. The original game consisted of three sandwiched plastic discs. One of the outer discs carried a labyrinth on the inside, the middle disc carried two pins which ran in the grooves of the labyrinth.
With this game 'Twin Maze' my plastic puzzle has been finally transformed into a board game.
 
 
More freeware as well as real puzzles and games at my home page http://karl.kiwi.gen.nz.