Very easy at the beginning, but Def becomes complicated and challenging sometimes. Defch, some ads here and there, but not a horrible amount. I would say that after every 3 or 4 puzzles there is an ad. They are about 6 seconds about 15 seconds. I have not found one that is still 30 years old. Until now very fun and very creative with the puzzles. Not bored at all. I love wonderful game. The main feature is missing: the ability to reproduce levels. I wish there would be a little more variety intermitted at early levels. Play a couple of other brain teasers, some other types of puzzles that could be added. The game is fun, occasionally stumbles and has some charm. I am enjoying so far. Funny and a bit peculiar sometimes ... concept different from most games, but similar to some games that I have seen ... but not as impossible as they! I feel that it is the fair amount of simplicity against the challenge for a light heart game. Perfect to liquidate and not have to think too much while having a feeling of achievement / feeling intelligent! LOL. Seriously, I have completed all levels, without internet, we can play this game and it is a wonderful amazing game ... My game without mind, relaxation, reflective game ... I loved it ... in general 684 completed levels ... Hip pip hurrayyyyy ... I need more updates waiting for it ... My God, this game is so good that it unlocks different levels every 5 minutes, so it never gets bored and there is a content.