In the Northern United States, specifically rural areas throughout Ohio and Michigan, small creatures with elongated heads called Melon Heads have been reported attacking people from the woods. According to the stories (which are all eerily similar), the Melon Heads were once orphans with hydrocephalus, a condition in which fluid builds up in the skull, and who lived in an insane asylum.
Through various circumstances—escaping from the asylum, murdering their doctor, becoming cannibals after the asylum burned down—the children turned feral and took to living in a system of underground caverns deep in the woods. What’s interesting is that reports have come in from vastly different geographic regions across state borders, and the legend in each state begins some version of the asylum story. There are dozens of reports from people who claim to have been attacked by bands of small, misshapen creatures with bulbous heads.