It is a 50-foot-square room with five pillars made of mortared humanoid bones, painted black. The floors of the alcoves where the grells hid are littered with the gnawed bones of past meals (mostly goblins and gricks). There is nothing valuable, magical or secret here, as far as Morph can tell.

 (Are there any other exits?)

No other exits in this room.

"Should we head south, then?" Laniel says.

Titus wipes the blood off of his axe and nods and begins to proceed south.

Rethan lets Titus lead and takes the rear guard.

The adventurers head back down the long hallways and turn south, finding themselves in the room with many pillars and the snake skeleton again.

"West or South?" Laniel says.

"Remarkable." Atuan exclaims, finding themselves so neatly turned around. "I wonder where those bandits must have been hanging around at, then. If all those passages weave back into each other, then they either have claimed a corner of territory that is little more than a knot, or they sit upon an entrance to a whole new section."

"Yeah it is getting a little confusing, and I'm keeping a very simple map of our travels so far."

"Its possible the thugs we run into in the north end, are hold up in whatever was up the stairs they ascended."

Morph looks between the west and south passages.

"I cant really see any reason to pick one over the other."

"My guess is that the warning about the south passage was for the raw un-reinforced section of tunnel, that was still being excavated."

"Maybe we try the west passage just to be safer? Less chance of a cave-in?"

Atuan blanches slightly at the thought of being buried under a mountain of stone and rubble, and nods at Morph's suggestion.

Laniel agrees and the party begins walking down the western hallway. Niches, each 3 feet deep, line the north and south walls. Mounted on the back wall inside each one is a large, oval glass mirror in a heavy stone frame — sixteen mirrors in all. The blackened end of a burnt-out torch lies on the floor in the middle of the corridor.

Morph casts Detect Magic to detect any on anything in the passage, but especially the mirrors.

Morph finds that three of the mirrors are magical as they pass by. Calling the group to a halt, he muscles his way to the front, examining the rest. Five in total appear magical. The first three appear be Illusion magic. The last two are Necromancy magic.

"5 of these mirrors are magical, these three are illusion magic, and those two are necromantic."

Morph points to the specific mirrors.

"I don't know what they do or what triggers them, but the necromantic ones have me especially concerned."

"Maybe we don't look to deeply into them?"

"Okay..." says Laniel. "I wasn't going to do that anyways."

(Did we see/notice anything odd about the mirrors while inspecting them int he first place?  Without going back to peer deeply into them :P)

(Well, nobody has inspected them as of yet. Morph has merely identified 5 are magical. Below: Yellow are illusion magic mirrors. Purple are necromancy magic mirrors.)

(I see.  Wasn't sure if anyone had actualy looked in them as we walked by)

(I would never presume. But casual glances at the mirrors revealed nothing.)

"Well, no sense in suspense."

After muttering a brief incantation (self-cast guidance), Atuan investigates one of the illusion mirrors. Specifically, he wants to see if the illusory mirror is real (i.e., not a mirage of some kind) or if its been enchanted with illusion magic of some kind. He begins by throwing a ball bearing lightly at it, after which he will risk looking into it.

investigation: 18  + 4