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[Spells help] call lightning

Syntax: cast 'call lightning' 

Call lightning brings forth a hail of lightning bolts on an
enemy group.  While the spell can be used in any weather, it is more 
powerful when it can call down lightning bolts from a storm.  The 
ideal conditions for calling lightning are when it is raining hard, 
warm and very windy.  The spell only works outdoors.

See also: 'control weather'