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Nightmare Fuel: The Adventures of Dr. McNinja
Time it right and you could reach the bottom of the page, look away for some reason or another (perhaps to drink your water or soda or whatever), and when you look back, your screen's coated with whatever you drank. Because you spit it all out in shock.
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.
The White House Nega-Zone. It's an ancient magical security system designed to trap intruders by playing off their own fears. But because everyone's so different, the Nega-Zone has to use easily understood symbols. So, sometimes you get stuff like the fear of death, and sometimes you get your teenaged sidekick.
In addition, the Nega-Zone works, draining you of all sense of self and trapping you forever, as this poor sofa can testify.
Not to mention that the ancient spirit running the whole thing is a little bitter about his current job.