Don't let appearances fool you, this is not a game only for children. It has the pleasant appearance and feel of a children's game but is a quite challenging puzzle game. The use of characters for puzzle pieces makes it easier to remember their weaknesses and strengths. The music is happy and relaxing and the theme is very positive. I have no finished it but I can go back to it anytime I feel like it and give the puzzle a try. It is not timed which is very important. You can collect stars but there are no points, not competition, just relaxation. Trial and error or mathematical thinking? Both work. The mechanics and navigation of the game are easy.