This is one of the large puzzle fest games out there in recent years.
You play an adventurer entering a strange castle where all actions are performed by a wand: you set the wand to a color combination, then you go on.
It has a fun feel similar to Grandma Bethlinda's Variety Box, by the same author. Slowly, more and more combinations are revealed to you, often allowing you to go back and do things that you've been wanting to do for a while, but were unable to do.
HIghly recommended.