Mothman is a very specific monster in that it only exists in one place, during a very specific point in time. In a small place, Point Pleasant, West Virgin,a from around November 1966 until December 1967, there were reports of a humanoid creature known as Mothman. It even has its own Museum.
That is a live YouTube camera, by the way, that shows the giant Mothman statue that is very popular at the Mothman museum. The sightings themselves have been explained by things such as the migration of birds in the area that don’t normally come through there such as sandhil cranes.
As you can see, the sandhill crane is a rather large bird with red/orange eyes, which lines up perfectly with what the Mothman reportedly looks like, a large creature with Red eyes and wings. If you were to see one at night out of season, you could, while scared and surprised, possibly confuse it for being humanoid.
Mothman has appeared in movies such as The Mothman Prophecies and is a staple in the Fallout games, and while I honestly belive there is nothing to this one, it is one of the more fun ones out there. Best wishes, and may the gaming gods bring you glory.
Savior Gaming 