Adding a cobalt shield wouldn't particularly make a difference. It gives six defense, adds thorn damage, AND adds extra minions. The minion thing is totally out of theme, but I suppose the thorns could make sense. If the thorns was true though, the defense would need to be much lower, like one or two.Hmm, How about adding a Cobalt Shield to the recipe?
Also, the later weapons are for the modded bosses, which will be harder than