The Horn of Helm
A simple wind instrument made from brass. If used by inexperienced
musicians it sounds like somebody making "prbbt!" noises down a drainpipe.
Heedless of cold, fearless of darkness -- besiegers fled at the wind of
the solitary coming of King Helm Hammerhand, proclaimed by a single
horn-blast in the dead of winter.
It can be activated for sound ball (300) every 300 turns if it is
being worn. It increases your strength and constitution by 2. It
provides immunity to cold. It makes you completely fearless. It
provides resistance to nether. It cannot be harmed by acid, cold,
lightning or fire.
Level 16, Rarity 10, 1.5 lbs, 15000 Gold

(T.o.M.E. 2.3.5)