Battle Chasers: Nightwar

There are two ways to do this trophy. The first is to craft one of the characters' ultimate weapons as they are all legendary weapons. The second is to wait until you are playing on new game plus and then craft an item, as you are able to go up to legendary (400%) on items on NG+. Whichever path you take, once you have crafted your first legendary item, the trophy will pop.