Blackburrow
 

At the zone line in Blackburrow, when zoning in from Qeynos Hills, there appears a large cluster of Gnolls.. They start walking off into the walls. They can be targeted but do not agro.

Someone made a train?

No Rogean, this is happening in many zones. Highkeep is one of them. You cannot attack the mobs, they will not return to their spawn points. Hobby had to summon a few of the guards in highkeep just so they can be killed.

I thought it was just an illusion, like the phantom mage pets that sometimes appear at zone lines that only some people can see (I think just people with the graphics update? Not sure). But yeah, what's being described is happening.

Saw this at highkeep also. Also witnessed this behavior from the frogloks in Guk

Also believe I saw this a couple of times in SolB recently. Not just normal train but bugged mobs.

Yep, I've seen a kobold and a fire giant bugged in this fashion in Sol B recently.

Just to clarify.. This would happen constantly upon zoning in. I could zone out and back in and they would reappear (possibly at the "safe spot" spawn?). They would then proceed to walk off into the walls and get stuck there walking.. most would disappear but occasionally one would stay there walking.. You couldn't attack them but could target them and they would not agro. Others in my house observed this on their account. I didn't notice this last night though (Sunday Feb 27) so it may have been addressed. We DID though experience weird training out of nowhere (and no, not because someone trained stuff on us) (this has been addressed in another post).