The Horadric Malus is a quest item needed to complete the Tools of the Trade quest. It is an enchanted smithing hammer that Charsi left behind when she fled the Rogue Monastery. When the forces of Andariel took control the Monastery, the Malus was entrusted to The Smith in the Barracks. The Horadric Malus is a thoroughly unremarkable as a weapon, and is much better used to complete the quest.