Olympia: The Age of Gods PBEM (May 4 1999)
Usage: USE 9160 [aura] Time to learn: 28 days. Time to use: 10 days.
Erects a magical barrier which prevents anyone from entering the location. The barrier will lose one point of strength at the end of each turn, and will dissipate when it has no strength remaining. The maximum strength for a magical barrier is 4 (lasting 4 months). The cost of casting this spell is the square of the strength, e.g., a strength 4 barrier costs 16 aura to cast.
Aura defaults to one.
Barriers cannot be cast on provinces.
When a magical barrier dissipates, lingering effects of the spell prevent another barrier from being cast on the same location for four months.