RETZ EDUCATIONAL ROLE GAMES

You already know this type of book in which you are the main character:

It all started with the disappearance of the eminent professor Bergier. Soon you learn that he has been kidnapped by the alien Atlas whose flying saucer is flying over Europe and who threatens to annihilate all European capitals. You must locate the 12 secret bases of the invaders, engage in combat, rescue Professor Bergier, destroy the enemy bases. How to act? Fortunately, Professor Bergier, at the risk of his life, at each stage of the saucer hides some clue about Atlas's projects. And then you will also meet another race of aliens: the Sphynx, specialists in puzzles. If you manage to decipher the professor's clues, if you know how to answer the Sphynx's formidable questions and if you prove to be a fighter full of energy and strength, you will triumph over these tests fairly quickly. Otherwise...

But it is also a useful book:

Indeed, each clue, each enigma directs you towards a place in Europe. And if you're wrong, you'll still find the right answer and details about the city, the river, the mountain... further down. So, win or lose, you will have learned, while playing, without tedious effort, a lot of things about the geography of our continent.

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