The spell Ghost Feet (page 90, in 2.6) has varying Power Levels. For one individual it is PL 1 or 5, or 5 individuals it is PL 3 or 7. It does not specify when you would use PL 3 over 1, or PL 7 over 3, as the durations are listed as 2D6 minutes (PL 1 or 3) or until sunrise (PL 3 or 7). When would I use a certain PL over another? Am I missing something here? Any help would be much appreciated.