A free app for Android, by Big Fish Games.

The Forgotten Books: Crown is a puzzle game in which the story is written in the form of a book. In order to save the world from the evil darkness, the player must solve a huge amount of challenging puzzles and riddles.

The story begins with the discovery of an ancient book that has been lost for centuries. The book contains a map that leads to a secret location. The secret location is hidden behind a secret door, which can only be opened with the right key.

In order to find the key, the player must solve a riddle. The riddle tells the player where the key is, but also tells the player how to get there.