anti magic shell ams

Usage:          cast 'anti-magic shell' [char in room, self only, npc, pc]
Duration:       3 hours
Waitstates:     2: MAG, SOR, LOR, SAG, NIN, SWO, WIZ, MON
Accumulative:   No
Violence:       Positive
Costs:          50 - 15 
Position:       Standing
AMS-State:      
Classes:        (L41)  MAG, SOR, LOR, SAG, NIN, SWO, WIZ, MON
Magic Sources:  n/a
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   This spell conjures a shell that shields the caster from most of the
forms of magic. There are spells that are able to penetrate the shell and 
affect the person inside the shell from the outside, some spells can be cast
from the inside of the shell to the 'outside'. Even some spells cannot be
casted from the inside at all.
Which spells can penetrate the shell in which direction is stated in the
help of the appropriate spells under 'AMS-State'.