In order to find the Dark Sword, you must find Dark Wraith knights. There are two locations that are certain to have Dark Wraith knights and they are both found in the Farron Keep area. One knight is found shortly after the Farron Keep bonfire a little ways into the swamp. Unfortunately, there is only one knight and the swamp is poisonous so this option can be quite a hassle.
The second location is your best bet because there are two Dark Wraith knights, and as long as you isolate both of them, you will have yourself a Dark Sword in no time. The bonfire you want to be at is the Farron Keep Perimeter bonfire. Along with being a safe place to farm souls, the Farron Keep perimeter is the best place to farm for the Dark Sword and the Dark Armor.
Head out of the passage way and towards the Abyss Watchers boss arena. On your left there will be two Dark Wraith knights walking up the hill. If you stand close enough to the one closest to you, he will run over and you can face him alone. If he does not drop the Dark Sword then go kill the other Dark Wraith knight. If that one doesn’t drop the weapon then head back to the Farron Keep Perimeter bonfire and start again. Wash, rinse, and repeat until the Dark Sword is yours.
There you have it, now you have one of the most sought after weapons in the game. The Dark Sword is extremely light and pretty long and wide so it has the best of both worlds in terms of reach and size. It is definitely worth your time if any bosses or areas are giving you trouble. Dark Souls III is out now for PS4, Xbox One and PC.
