Creatures in the warded area take a −5 penalty to Stealth checks and Thievery checks. Your Arcana or Religion check determines the size of the warded area. The warding effect lasts for 24 hours, but you (and not any assistants) can extend the duration by an additional 24 hours for each extra healing surge you expend just before the current duration expires. You need not be in the same area or even on the same plane to extend the duration. If you extend the ritual's duration for a year and a day with­out interruption, the effect becomes permanent.