i played gothic as i was like 10 in 2002.
Its an RPG where the world map is limited by an "macigal barrier" that kills you if you try to pass it.
I didnt realised that its just a computer game and thats the "map". I really thought there would be a complete world outside of the barrier (like it would be in real life). Also the atmosphere and credibitly on that game are fantastic.
So I tried several times to pass the barrier and discover the world. Some day i managed to do it by using cheats. I realised that there is no "big world" but just the border of the map and i felt in the skybox.