The Halberd 'Osondir' (+6, 5d5)
+3 to charisma. It increases resistances: +25% fire and +25% sound. It
modifies damage: x2 vs. undead, x2 vs. people and x2 fire brand. It gives
its wielder feather falling and see invisible. It is vulnerable to damage
by disenchantment.
Level 20, Rarity 8, 21.0 lbs, 11000 Gold.

(EyAngband 0.5.2)