Nightwielder was an Asian high Epic who was a part Steelheart's inner circle (his right-hand to be precise). He gives off a garlic-like smell when he's nearby. He was killed by David by shooting him when tangible. Megan stated that she never liked him and Steelheart said he'll be difficult to replace.
Nightwielder could become incorporeal, allowing bullets to pass through him, giving him a "prime invincibility," as David puts it.
Darkness/Shadow Manipulation Edit
Nightwielder could control a special black fog that he can solidify and pass through solid objects at will. This fog looks like darkness. He plunged Newcago into eternal night.
Nightwielder had the means of flight. This might have been related to his intangibility.
Nightwielder's weakness was UV light. Any form off UV light could make him corporeal. When Newcago was plunged into darkness, Calamity was the only thing that shone through Nightwielder's darkness.