This papercraft is Met (Mettaur or Metall), a shortening or nickname that came from the original Mega Man NES manual, a recurring Mechaniloid enemy from the Mega Man series, the papercraft is created by Julio Cesar.
Their actual names were rendered in English as Metall or Mettool in earlier appearances. They didn't have a consistent localization in English until 2004 when the name Mettaur was used in all western Mega Man games since. They are also unofficially called Hard Hats in some strategy guides. Mets contain an indestructible hard hat that makes them invincible while hiding under it, although a few games allow the player to bypass this. For example, they can be flipped with Oil Slider in Mega Man Powered Up and with guard breaking attacks in Mega Man X8.
These robots have appeared in almost all of the Mega Man game series, except for the Mega Man Legends series. They mostly appear as enemies, but there are also bosses such as the giant Met in the Wily Castle in Mega Man 4, Metall Daddy. In Mr. X's Castle in Mega Man 6 there is a Met boss operating a tank, named Metonger Z. In Mega Man ZX, there is a giant Met sub-boss, named Powmettaur. [Source: wikia]