SRD:Helm of Opposite Alignment
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Helm of Opposite Alignment: This metal hat looks like a typical helmet. When placed upon the head, however, its curse immediately takes effect (Will DC 15 negates). On a failed save, the alignment of the wearer is radically altered to an alignment as different as possible from the former alignment—good to evil, chaotic to lawful, neutral to some extreme commitment (LE, LG, CE, or CG). Alteration in alignment is mental as well as moral, and the individual changed by the magic thoroughly enjoys his new outlook. A character who succeeds on his save can continue to wear the helmet without suffering the effect of the curse, but if he takes it off and later puts it on again, another save is required. The curse only works once; that is, a character whose alignment has been changed cannot change it again by donning the helmet a second time.
Only a wish or a miracle can restore former alignment, and the affected individual does not make any attempt to return to the former alignment. (In fact, he views the prospect with horror and avoids it in any way possible.) If a character of a class with an alignment requirement is affected, an atonement spell is needed as well if the curse is to be obliterated. When a helm of opposite alignment has functioned once, it loses its magical properties.
Strong transmutation; CL 12th; Craft Wondrous Item, creator must be 12th level; Price 4,000 gp;Weight 3 lb.