Lodestone Trap CR 2
Type magic; Perception DC 21; Disable Device DC 21
Trigger location; Reset automatic
This large circular stone chamber has four massive iron doors in the north, south, east, and west walls. The south and east doors stand open, while the north and west doors remain closed. At the center of the room a strange stone obelisk rises from floor to ceiling, its surface covered with metal bands and encrusted with deposits of a strange greenish mineral. The floor of this chamber is strewn with headless skeletons and scattered bones (no skulls among them). A dented steel shield and bits of metal armor lie at the foot of the obelisk. This large circular stone chamber contains a complex trap. The doors on the south and east walls of this chamber are framed with heavy iron doors on swinging hinges, which open away from the chamber, but brace against the masonry doorframe and jam shut if pulled or pushed toward the chamber’s interior. The north and west doors are reversed to be pulled open inward (although they are very heavy).
The obelisk is a giant lodestone whose magnetic properties are activated when more than 30 pounds is applied to any one of dozens of pressure plates on the chamber floor. There is a specific safe path through the chamber, which involves skirting the circumference west and then cutting a path east after passing the obelisk and looping back south to the eastern exit. Anyone stepping on a pressure plate unleashes a magical discharge of energy and takes 1d6 electricity damage. This charge also activates the powerful magnetic quality of the obelisk. The entry doors are yanked shut and jammed by the magnetic pull, just as those over the alcoves are wrenched open. Anyone wearing metal armor is dragged 10 feet toward the central obelisk every round (DC 10 Strength check to resist this pull, DC 15 Strength check to move normally, although half speed away from the lodestone). Once pulled to the obelisk, such characters are pinned (as in a grapple). Success on a DC 10 Strength check is required to take any action, and a 15 on the check allows a character to pull free of the obelisk. Metal objects secured on a person are ripped free and cling to the obelisk. Metal objects gripped (shields or weapons) are wrenched from the hands of anyone failing a DC 10 Strength check (even if this check is made attacks made with held metal weapons have a –2 penalty). The lodestone retains its magnetic quality for 1d4 minutes but can be deactivated earlier if it is struck with a second electrical discharge.