Had a boss monster blocking the gate on lvl 3. While searching for that gate, got dropped to the 6th level. Already used the teleport stone earlier for a town invasion (still lost the apothecary). No sooner do I hit bottom, surrounded by a mob far away from the ladder up, when there is a town invasion... Soon followed by another "coordinated" town invasion.
As townfolk are dropping like flies, I got the hint and gave up on the town.