The hall was curious, complex, and clearly designed to prevent passage across it.
At either end of the hall, identical circular rooms with mirrors and a statue at the center capped a long hallway filled with lava.
(Lava: insta-death. Bad)
Clearly there was a trick involved with the statues and mirrors.
The statue was of a human, older, with a full beard, dressed in elaborate robes. His arms were folded across his chest.
After testing several theories, the eventually tried rotating the statue at the base.
The statue turned.
After a minute, they realized that the statue in the other room turned also, to match.
Soon, with trial and error, they realized that the reflection in one of the mirrors in the hall was different from the statue it self. When the statue faced that mirror, the hands, which were folded across the chest where now held out in front of him, with the hands cupped on other the other, palms slightly apart.
The statues would only face the mirror for a short time before resetting to face the entrance.
While the statue faced the mirror with altered reflection, gravity in the hall way reversed allowing a person to traverse the hallway from the ceiling.
Pit traps made rushing across the hall hard to hurry across before the statues reset.
The party was innovated to buy time by holding the statues firm while others crossed.
All went swimmingly until flex fell into one of the pits. He managed to miss the spikes at the bottom, but he suddenly realized that gravity reversed back. He fell backwards toward the reversed gravity. And, back and forth, until he stabilized in the center.
Kahseer wild shaped in to a giant spider, climbed across the ceiling, down the pit, webbed a totally-freaked out Flex, and pulled him to safety.
It all could have gone so much worse.