Prince Adam of Eternus, also known as He-Man, is a fictional character and the main protagonist of the sword and planet Masters of the Universe franchise, which includes a toy line, several animated television series, comic books and a feature film. He-Man is characterized by his superhuman strength and in most variations, is the alter ego of Prince Adam. He-Man and his friends attempt to defend the realm of Eternia and the secrets of Castle Grayskull from the evil forces of his archenemy Skeletor. The character was created by designer Roger Sweet, who intentionally created the character in such a way for him to be abstract and generic enough to be applied into any context and genre; Sweet also chose the name "He-Man" for being generic. Presenting three different versions of the figure to Mattel—including a soldier and a spaceman—the barbarian version of the character was chosen and developed into the character's current form.