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Nightmare Fuel: Sparklehorse
Grim Augury has some nasty gothic imagery in its lyrics.
The tiny, little-known B-side "Haint" is just... well, don't listen to it before going to sleep, let's put it that way.
It's up in the air how accidental it is, but Good Morning Spider (the song) is creepy as fuck when you notice the quiet, indistinct radio chatter in the background. Same goes for Sunshine, and in fact several of the songs on the album.