Comparable to chapter 1's knife.

Still neutral, still 1 resource. Discarding no longer gets you a useful +2 to hit, but you don't decide until after you hit.

Is it a card you would ever include in a deck if you have access to any other method of dealing with enemies? No.

Is it a card-shaped piece of cardboard if you need to proxy something? Yes.

Do we need 10 copies? Not unless something happened to the rest of your cards.