Sauron is a being of many forms and appearances. As Halbrand (Charlie Vickers) says in “The Rings of Power” series, the character has been around since the breaking of the first silence (i.e., the beginning of creation), and in that time, he’s had many names. Those names have come with a variety of appearances. At different times, Sauron dons an angelic form as well as that of a wolf, serpent, monster, and bat-shaped vampire. He also operates as the shady Necromancer and in a more intimidating humanoid form later in life. Those last two are for a specific reason. By “The Lord of the Rings,” Sauron has lost his bodies so often (and poured so much power into the One Ring) that he can no longer take on any humanoid form easily.
Sauron completely loses his body twice at the end of the Second Age alone. After the first of these physical destructions, “The Silmarillion” says, “He wrought himself a new guise, an image of malice and hatred made visible.” It also says that by this time, “He could never again appear fair to the eyes of Men.” Interestingly, while describing a full-body reincarnation, the text also calls out one bodily feature above all others, saying, “and the Eye of Sauron the Terrible few could endure.”
This is the point where Sauron really starts identifying with the terrifying eye element of his persona. His soldiers paint the Lidless Eye on their helmets and banners and use it as a form of graffiti. But even then, there’s no indication that Sauron is only an eyeball. In fact, this starts before the One Ring is cut from his hand, when it’s pretty safe to assume that he has a full body, fingers and all.
