Armor of Vulnerability
This armor seems to be genuine, magical armor with a protection factor of +1 to +4 - but the factor is actually -1 to -4 . The vulnerability of such armor is not revealed until an enemy strikes a blow in anger at its wearer.
This appears to every test to be magical plate mail +1, +2, or +3, but it is actually cursed armor -2, -3, or -4. The armor's great vulnerability is not apparent until an enemy successfully strikes a blow in anger with desire and intent to kill the wearer. The armor falls to pieces whenever an opponent strikes the wearer with an unmodified attack roll of 20.
Item type
Armor