The Ring of Power 'The One Ring' (+15,+15)
Permanently cursed. +5 strength, intelligence, wisdom, dexterity, constitution, charisma, speed. Provides immunity to acid, lightning, fire, cold. Provides resistance to acid, lightning, fire, cold, poison, dark, nether, disenchantment. Cannot be harmed by acid, electricity, fire, cold. Sustains strength, intelligence, wisdom, dexterity, constitution, charisma. Speeds regeneration. Grants telepathy. Grants the ability to see invisible things. Aggravates creatures nearby. Drains experience.
When aimed, it does bizarre things. Takes 209 to 650 turns to recharge.
Min Level 100, Max Level 127, Generation chance 1, 0.2 lbs

(Angband 3.1.2v2)