The real Knife Eye Attack. It's not wearing knives over your eyes... it's seeing everything, absolutely everything, as knives. Think about it. Seeing the normally calm Dan McNinja utterly terrified is kind of a shock.
Dan:Get away from me! You're made out of knives! He's turned everything into- (Mitzi knocks him out for his own safety)
When King Rad's doing something cool, he usually has a suave grin on his face. In "A Cumberland Doctor in King Radical's Court", though, a lot of his smiles are turning into Slasher Smiles, especially when he's revealed that he's been killing people for his ritual.
Hey? Are you an average Joe in the Doc's universe? Too bad. King Radical has decided that you're not cool enough to exist in his new Radical Lands, and you will be killed so someone cooler can take your very existence.