Written on the wall of the exit to the chamber was the words "Test your strength."
"Noooo, another test!" cried Tiggy. "I can't take any more!" she added dispairingly. "I've been dropped, stabbed and attacked by a shambling mound and I'm losing the will to breathe this foetid dungeon air."
"Don't worry..." said Elija patting his visibly shaken friend, "it'll be over by Christmas." he kindly suggested.
"That had better not be a Dwarven christmas", pointed out Stamm. Dwarves suffered from the lack of both Christmas spirit and follow a calender that extended past the lifetime of many humans adding to their dark mood and a sparcity of good will (aka 'presents').
"Wait a minute, though. We all should know how to beat this one, don't we?", said Iaido. To the one side was a closed door, and sure enough the corridoor advanced to the darkness yet they couldn't advance due to some invisible barrier blocking their way.
What to do?
* Just like the author did, when he was a stupid fifteen year old, back in 1987.