... it's LARPing at Moszna Castle: The Witcher School
The Witcher School is a LARP for adults inspired by "The Witcher" series and the fantasy book series by Andrzej Sapkowski.
During the game you will become an apprentice going through a rigorous witcher training: you will learn fencing, archery and alchemy; you will hunt monsters, unveil secrets and intrigues; and finally, you will face tough choices and discover the consequences the hard way. You will move to Moszna Castle in Poland, redecorated for our needs and transformed into a real witchers' abode where you will meet famous characters known from "The Witcher" books and games.
The "Design Document" goes on to elaborate:
Up to this point, you could only read about this or see this on the screen of your TV or PC. But here... if you want to slash your enemy with a sword you do not have to imagine doing that, or push a button on your controller. What you have to do here is to do it for real. You will learn how to brew potions using real ingredients, and what gestures are needed to use witcher signs. And these are only a few of the things you will be able to learn. You will be an integral part of the live action. This will be an opportunity to immerse yourself in a well-known setting of The Witcher and live your own unforgettable adventure.