Icewell: pets warp and Councilors don't get enough sleep.
 

Sending a pet on Councilor Darakor (for example) in his room will make the pet warp to the top floor and aggro an army.

Also often times, Chamberlain will shout assembly is over but Councilors won't go to their rooms at all (or just some).

pets popping into different levels used to happen in unrest, i think it was fixed there

At the very least, it is very easy to reproduce in Icewell Keep.

Make an epic mage pet (I don't know if the size of the pet matter, it will work with the epic one though). Waltz up to Councilor Darakor, and send pet on the mob. A few seconds later the pet will be on the top floor with half the zone raping you.