I haven't seen threads about this room so far, so I started a new one. I hope I didn't miss some thread or some posts (apart from those in the bug tracker, I mean).
The history so far (aka how it all started):
TB actually introduced this special room in p9, in response to a suggestion, but a nasty bug got in the way until p10.
The message:
When you enter a dungeon level that contains the special room, you receive the message "You feel a surge of pulsing power".
The room:
A disconnected room, similar to royal vaults, but filled with monsters that guard an artifact instead of gold. I found one in UD5 and I took a screenshot after reading a scroll of magic mapping:
In my case, I found mummies, fire drakes, ratling master thieves, doppleganger lords, berserker lords, a white baby dragon and a lightning vortex, and a named doppleganger king on top of the artifact at the center of the room (the hammer of the gods).Code:############# ################################### ######### #........./.# #...../...........................# #.......# #....>....#.###.....###.#######################.#####.......# #.........#........./.......................................# ######### #######/#################.################################### #.......# #.# #.......# #.......# #.# #######.##### #.......# #.# #.....# #.......#########.###########################.### ############# #.........................../........./.........# #...........# #.......#########.###########.........#######.#.### #...........# ####### #.......# #.# #.........# #.....# #._..@......# #.....# ######### #####.##### #.........# ###.#.###...........# #.....# #.........# #.........# #...../...........# #..(..# #.......<.# ########### ################### #.....# #.........# #.....# ########### #######
I guess we need a name for this type of room. At first, I thought of "artifact vault", because of the similarity with royal vaults; however, we find artifacts in traditional vaults also. Maybe "artifact chamber"?