Acid Pit Trap

The floor ahead is rough and uneven.

The floor is stone-covered plaster or flimsy wood concealing a 30-foot-deep pit. Placing more than 300 pounds of weight on the floor (typically by two or more Medium creatures walking on it at once) triggers a Critical Failure. The pit can cover any area of floor, from a 5 by 5-foot pit blocking a narrow hallway to a 50-foot-wide pit that fills an entire room.

This pit is filled with acid. Creatures within 10 feet of it hear a faint hissing sound, though they can’t necessarily pinpoint its source. A Perception check or an examination of the floor allows a creature to detect a faint acrid smell and identify that the hissing comes from below.

There’s a 25 percent chance that the pit contains the remains of previous adventurers, along with a Minor Treasure.

Exploration. A Perception or Investigation check reveals that the floor is unstable, or that there are no signs of travel through this particular area. Probing or tapping the floor above the pit reveals that the area below is hollow.

Keeping Clear. Once discovered, the pit can be bridged or circumvented. The party can travel over the pit one character at a time. Only a Large creature or one wearing heavy armor triggers it on their own.