The Shimmersand puzzle, located 6412, 7720, is a game of Pet Solitaire. To complete this puzzle you must turn off all of the lights besides the center light (which at the start is off). The way you turn off lights is by right clicking on a lit light and then clicking on a turned off light. The catch is that you can not click on a turned off light directly next to the lit light. There must be another lit light in-between the lit light and the non lit light. Also, when you “move the light”, the light that was in-between the lit and non-lit light will turn off.
This puzzle, as you can probably tell, is rather hard to explain with words, however when you try this puzzle you will instantly understand what I have been trying to say. As for a true click in this order guide, I can not give you one. There is a lot of trial and error with this puzzle and it may take you a few times before you complete it, but with logic and patience you can beat this puzzle too.
For a step-by-step full solution, please visit this site.