The entire room is suspended in a vertical shaft, held in place by massive counterweights. Anyone entering the central ring of pillars will trigger a release mechanism, allowing the entire room, floor, walls and ceiling a single unit, to slide down the iron pillars, cutting off retreat through the doors after a single round.
There are several possible variants of this room:
- It could be a simple elevator-style trap, splitting up the adventuring party unless they can find a means to raise the room back to the main level.
- Once lowered the room could provide access to additional doors out of the chamber, revealed by the gaps in the walls.
- The entire room could be suspended over a pool of water or oil, which rushes into the room through the central well when the room drops. Those within the room must find a means to escape before they drown or accidentally start a fire.
- The central well could actually be a means of egress, but only if the room is lowered, its weight opening a trap door beneath the well.
- The well could provide access to a creature or creatures that lurk below the room, waiting for the mechanism to deliver them fresh prey.
Once the room has dropped its full distance anyone left behind can cross the roof of the room to gain access to the door originally on the far side of the chamber.
Depending on the variant(s) chosen, the mechanism to raise the room could be a simple timed device or a mechanism hidden away elsewhere within the complex.