Meet the snoligoster, who feeds on the shadows of its victims. The whirling whimpus, who once laid low an entire Boy Scout troop. And the hoop snake, who can chase prey at speeds of up to 60 miles per hour and then, with one sting of its venomous tail, cause it to turn purple, swell up, and—alas—die. These and 17 other fearsome creatures are among the most fantastical beasts in American folklore. Their stories, as narrated by one of the last surviving cryptozoologists, are best enjoyed while sitting around a campfire. If you dare.