While as an initial idea it is good, I don't know who... crazy scientist thought that with a watch battery (takes a round plate) it could work for more than 5 minutes a little motor that gives movement to the game! Of course, after a short time from the moment our cat started playing, the battery gave up.
Besides that, it sticks relatively easily on carpet, but it works well on smooth surfaces (tiles).
It's a shame that it's not worth the money because the cat seems to respond. With a more appropriate battery, it would be much better.