From the back of the book (translated with deepl):
Do you ever wish you could travel to faraway lands, explore strange planets, recover valuable treasures, uncover ancient secrets, rescue princesses from the clutches of mystical monsters, and put a stop to evil villains - in short, have all kinds of adventures without leaving the safe comfort of your living room? Then, of course, you can immerse yourself in an exciting book or be captivated by an action-packed movie.
However, if you would rather actively participate in the action instead of being condemned to passive watching, then you should definitely try out a tabletop role-playing game, also known as a tabletop role-playing game, pen & paper role-playing game or RPG for short, with your friends. Because unlike other board games or computer role-playing games, in this hobby you decide for yourself what happens in your story and how the world changes through the actions of your game characters, bound only by the limits of your imagination.
Like most games, however, role-playing needs a minimum set of rules to ensure fairness and a certain level of comprehensibility, so that events are not merely arbitrary. And it is exactly such rules that Gaudium Ludendi offers you. So open it right now and take your first step into a new, adventurous world...
More info available on the publisher´s website:
https://www.gaudiumludendi.de/01welcome/index