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Nightmare Fuel: Dumbo
CHASE 'EM AWAY...CHASE 'EM AWAY...
The infamous "Pink Elephants On Parade" sequence. This, children, is why we do not takehallucinogens (though "pink elephants" are more associated with someone being drunk rather than high). Consider the following facts:
Dumbo is actually hallucinating because he is drunk. An adult understands this immediately, but most children don't, since they've never been intoxicated. This aspect makes it even worse, because children are usually afraid of things they don't understand! If they are able to relate to it all it might be because Dumbo's hallucinations are similar to fever nightmares. In fact, most people to this day are afraid for this reason because it is unknown if it was meant to be enjoyable fun, the animators were high or genuine Nightmare Fuel.
What makes this scarier is that Dumbo was merely making funny shapes with bubbles, which then leads to one bubble turning into a pink elephant and the madness begins...
All the elephants are varied in color (but are mostly pink), but all have no pupils, causing them to resemble ghosts. Especially since the background is pitch black, like the night.
In addition, the elephants take on all kinds of bizarre and physically impossible shapes. Hopping over each other, walking into each other, changing color, growing and shrinking, floating in the air, walking upside down, growing extra heads, changing into cars and other vehicles... A Trope Codifier of Deranged Animation.
The scene where the elephants walk upside down on the ceiling, while another elephant sees them from his bed and then hides himself beneath the blanket from fear. This is one thing many kids did after watching this movie.
After the belly dancing elephant dissolves a disturbingly realistic eye appears in the middle of the screen, staring back at you. It's the only non-elephant appearing on screen in the entire segment other than a snake that changes into the belly dancer which dissolves into the eye. (The snake in question—a rearing cobra!)
The music is very creepy as well. But the lyrics, oh boy: "Chase 'em away! Chase 'em away! I'm afraid! Need your aid! Pink Elephants on Parade!"
The climax, oh god, the music for the most part has an eerie calm till the elephants decide to change to change into vehicles and the black scene flashes pink as they rush like mad, leading to an explosive conclusion leading to the second to last scene.