For convenience they are divided into six categories: logic, math, MENSA society riddles,history, science and extra . When you start game there is only one opened riddle in each category. Right answer to any riddle will give access to the next two. Solve riddles, find answers - open new achievements. All achievements will be saved in "Profile". Also, if riddle is too difficult and you can’t find answer , there is an answer button which show you a solution. But there are only 10 answers, so use them thoughtfully. In each category there are five "Bosses". To open them you need to solve certain quantity of riddles in each category. “Bosses” are more complicated than ordinary riddles. But when you solve them you can get special achievements, that will open the mystery of Da Vinci and interesting facts about him. You can try "Pro" version with no ads and with more levels ! Play throughfully! Follow us: http://www.facebook.com/PlanemoStd https://twitter.com/planemo_std