It's a pen&paper roleplaygame, situated in a world named Aventuria and somehow similar too the earth of the medieval ages. However, there are magicians, orcs, vampires, demons and other nice creatures. You play it with a group of friends and everyone plays one character.
Everyone tries to play his character as realistic as possible, for example my mercenary who hates the worshippers of the god Praios will always try to treat them as bad as he can without being attacked. But since he once made a pact with a demon he has to hide from them because if they realize what he has done they'll chase him through Aventuria.
