The most addictive games are usually the most simple and Lumen is definitely one that's hard to stop playing.
However, although it's simple when you get going, figuring out how it works is not so simple. Fortunately, there are detailed and clearly explained instructions about how to play it in the Help section.
The aim of Lumen is simple - bounce lasers around and maneuvering them through obstacles. You do this with a series of laser canons and deflectors which guide the beam.
You have to drag and drop the components onto the plan in the most effective way in order for the beam to pass through all the required checkpoints.
What makes Lumen interesting is the fact that users can upload their own obstacle courses and challenges meaning there is a huge number to choose from.
The only criticism I have of Lumen is that that playing area is rather small. It would have been far more challenging and interesting if the developers had expanded the game to fit the whole screen.
If you find the courses simply not challenging enough, then why not create your own and submit it to the Lumen database?
Lumen is definitely addictive once you've mastered the basics although there's plenty of room for improvement.