Since players cannot wield this, how about giving it to one of the freeport guards, or one of the antonican bards that so many people like to kill. Boy would they get a surprise when they attacked the npc who had this.
Then, with the difficulty to obtain, I suppose I'd hold it for a year or so, to see if someone discovers a quest that involves it.
Realistically, I cannot imagine that this weapon will EVER be made player usable. The damage output, with a good haste item, a bard and spell haste, would be insane.
TO take this guy down, they must have had multiple clerics chain casting complete heal on the main tank, and staggering the casts, because one cleric couldn't heal fast enough to keep up with this damage. Makes me sweat just thinking about it.