Nightmare Fuel / The Scooby-Doo and Scrappy-Doo Show

• In "Stowaways", right after Shaggy, Scooby, and Scrappy escape the ship in a lifeboat, there's a little lull in the action, panning down from Scrappy's face to the bottom of the lifeboat... when suddenly a huge shark blasts directly through the wood, eating the camera. It could make the viewer really jump, especially if they're scared of sharks.
• A lot of the villains Shaggy, Scooby, and Scrappy meet actually qualify. While normally it's mostly an angry beast with which they got on the wrong foot^note Which can still be frightening, depending on how jaded you are, more often than not it's a quite ordinary human being who wishes to trap, maim, or in some cases implied to kill them for the pettiest of reasons, or even just for fun.
  • Some of these human villains are actually implied to have preyed on humans before, again simply For the Evulz. It does not disclose what became of the previous would-be victims. Shaggy, Scooby, and Scrappy are essentially going up against at least attempted serial killers in these episodes.
• For example, The Waxmaster from "Wax World", who quickly reveals that he wants to turn the three into wax statues, which, given the Wax-Statue Making Process, is not a nice way to be immortalised...
• Slightly creepy one at the end of "Moonlight Madness" after the moon-activated necklace that was causing Shaggy to turn into a werewolf gets knocked onto the butler's neck as the trio flees. The butler calls out to them, "Wait, wait! Don't leave me, I'll feel so all alone!" Then the clouds uncover the moon and he turns into a werewolf. A second later, he turns back and says:
  "Funny. I don't feel so lonely anymore. I have me to keep me company!"
  • Immediately followed by the butler rapidly alternating between forms.
• "Scooby's Luck of the Irish" had a surprisingly creepy-looking Banshee.