So a few times now, I've been playing and running into random invisible walls that prevent you from moving forward. Like they're not there when I go into a closed off space, but when I try to leave it suddenly I can't move past an invisible barrier that wasn't there before. One such place I discovered was in the Labyrinth in Dragonspyre. In the far end of the map while looking for the Stone Rose I went into the corner at the end of the map. Two staircases leading down into an enclosed area, just past where the Gallum Knight spawns for the staff collection. I was allowed to go in, but couldn't leave. Invisible walls spawned on each side of the stairs trapping me in the section of that map indefinitely.
Luckly teleporting out and back in reset me to the start with no progress loss, but that was quite scary. I'm not sure if other such walls exist else where.
