Boneblade is a level 4 dagger in terms of magical enchantment and not a generic enchanted weapon. It can inflict 1d4 +4 points of damage and it has -4 THAC0, a speed factor of 0 and it weighs 1 lbs. This item appears in Baldur's Gate II: Shadows of Amn and Baldur's Gate II: Enhanced Edition. It is dropped by Qilue in her home when you kill her under Aboleth's orders in the Drow city of Ust Natha.