The Mattock of Nain (2d8) (+12,+18)
+6 strength, infravision, tunneling. +30% to searching. Slays orcs, trolls, giants, dragons. Provides resistance to dark, disenchantment. Cannot be harmed by acid, electricity, fire, cold.
When aimed, it turns rock into mud. Takes 2 turns to recharge.
Min Level 60, Max Level 100, Generation chance 12, 24.0 lbs

(Angband 3.1.2v2)