Seth was forced to stop and directly fight those shadow specters. He initially wanted to separate them and take one by one, but this method wouldn't be so effective, now that he realized that the clones were faster than him.
He chose to quickly dash towards the closest clone, swiftly striking him with his fist, making it instantly dissipate. That clone represented Eleventh Shadow and he only served as a fodder. Three of the other enemies took that opportunity to advance towards Seth, trying to strike his back with a dark elemental technique.
Seth had his attention on them all the time and before they were able to reach him, he turned around and attacked while using his leg to destroy them all. His movements were faster than what those clones were able to accompany, resulting in a swift strike that made the three of them dissipate.
