I was on level ten, proceeding from
coordinates 25,5 to 25,4. The hallway was
empty, but when I moved into 25,4, I was
ambushed by monsters that weren't there!

It was actually rather annoying, as I was in the
process of using various healing items to
restore my party's health before proceeding
deeper into the level. I had them moving up
and down that supposedly empty section of
labyrinth as they gained health from their
magical apparel. The un-looked for ambush
set me back a fair bit, especially since most of
my party could not fight to full capacity
because they were wielding Staffs of Healing
instead of their customary deadly weaponry.
Neither were they fully protected by their
helmets, shields, cloaks, and boots of healing
as they would have been by their higher AC
equipment.

This wasn't my first time on level 10... I've fully
explored the first section of it and found the
silver key, and I'd employed this tactic of
moving around empty hallways to restore
health in the past as well. Was this ambush
by invisible forces a freak occurence and a
bug, or is it something I can expect to
encounter again?

Grishny