Okay, the energy moving actually seems to amuse the hell out of him. It didn't matter that his dark energy couldn't get out of the little bubble they were in. He has also noticed those eyes on him, watching him. Not something that he was used to. Not unless they were his father's spies to make sure he did what he was meant to.

The weapon, itself, seems to come out of nowhere. Or it's possible that it comes out of the dark energy itself. The shape of it looking exactly like a crescent moon, if it wasn't a scimitar it would probably look harmless. Or like a mortal's boomerang.