Summon fog [826]
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Usage:  USE 826 <aura> ["Name of storm"]

Required aura:  three or more points
Time to cast:   seven days

Summon a fog.  Fog may be summoned from forest, swamp and ocean
provinces.  Once a location has produced a fog, another fog may
not be summoned from that place until the first has dissipated.

The fog will have a strength of twice the amount of aura invested
in its summoning.  Storms lose one point of strength at the end of
each month.  When a fog's strength reaches zero, it dissipates.

While the fog exists, the summoner will get a location report for
the province that it is in.

Character sightings will not appear in foggy province's location
report.  Characters in sublocations of the province will still
be seen, however.  Consequently, automatic HOSTILE attacks do not
function in provinces when fog is present.

Also, all sublocations of a foggy province are treated as if they
are hidden.  Thus, if a sublocation is already known to a character,
the character will continue to see the sublocation.  However,
locations which have not been visited by a character will have to
be found with EXPLORE before they can be entered (or until the
fog passes.)