Alkali Lake Monster
Nebraska
Also known as the Walgren Lake Monster, and granted the faux-scientific taxonomy 'Giganticus Brutervious'.
It is described as a dull grey or brown beast resembling an alligator, but vastly larger and heavier. It measures forty feet in length and possesses a distinct rhinoceros horn situated between its eyes and nostrils.
Endemic to the alkaline waters of Walgren Lake near Hay Springs, Nebraska. Modern biologists propose eyewitnesses simply saw an unusually large beaver or mudpuppy.
It comes ashore daily to devour large numbers of ducks and livestock. Its massive weight causes the earth to tremble so violently that farmers become seasick miles away, while its breath creates a thick, green mist that severely disorients passing travelers.
Fundamentalist Christians theorized the beast was placed by Satan to test the faith of locals. In reality, the legend was completely fabricated by John G. Maher, a notorious Nebraska politician and newspaperman known for perpetrating massive media hoaxes to sell newspapers.