This is based on opinion. Please don't list it on a work's trope example list.
Nightmare Fuel / The Sorcerer's Apprentice
Horvath exiting the Grimhold for the first time. He's made of cockroaches.
That's nothing compared to Morgana, she was made of black mud!
Poor Abigail, she may have been responsible for the "Salem Witch Hunts" but. I agree with Harry Dresden, evil or not. You shouldn't mess with kids.
"Poor Abigail"? She's like something out of a nightmare.
True, Drake was probably the more sympathetic out of the two.
The parade dragon turning into a real dragon. What's scary about it you ask? What the dancers go through. We see the inside of the parade dragon transform into a stomach while the dancers are inside it.