I picked this up on the 7th of July, off the 1st lvl shadow Knight, about 10min before Befallen was reset. It is very nice, not as much dmg as my cystallized sword but for the bonus, a good off hand weapon...
This item can be found in Befallen, on random servants, though it seems to be a rare drop. I've been hunting there for a few days solid now, and it is the first time I have seen the item.