It hasn't happened twice so don't think that this is a full glitch but very odd, I was looking to kill some time by looking for a tower to fight in that I liked when I was walking on the side walk and there was a gobbler gorger who had walked to the sidewalk and walked past me without even catching me for a fight. Very odd....
I did not have much time to take a screenie because it was like half of a second but it was very odd, and then as a stood I saw some of them stop for like half a second at where they would just turn around if no one was there...just odd
The Wizard101 server periodically sends your computer the location and facing of enemies as they move around. Sometimes, these updates get lost on the way. The Wizard101 game simply has then continue on the same heading until an update reaches your machine. Usually, their movement makes sense. Sometimes, especially if you have a bad internet connection, enemies will walk off into sidewalks or buildings. The server decides if you are in position to get pulled, so you are still safe on the sidewalk when you see this happen.
As Cole highlighted, this is a very old glitch within the game.
I must go on to say that this glitch in particular, occurs frequently when you're having net connection problems. So, whenever you see a mob just strolling on sidewalks or within the middle of battles, it's probably a sign that your net is starting to act up. So, in that case, this glitch isn't so bad after all since it warns you about you connection status.
Lol this happened on my old macbook (2009) I'd be in mooshu fighting pigs and all of a sudden they'd run out of bounds past the fences. Sometimes where enemies normally were, it'd be all clear. Lol
I now have a macbook pro (2011) and it seemed to stop. Mind you I had the same internet I had when I had the 2009 macbook.