Lord of the Rings: Rings of Power has a few possibilities for the most sinister character, but everyone knows who the main villain is. The Dark Lord Sauron is always lurking in the background of every story that takes place in Middle-earth, and he was behind almost every disaster, war, and family tragedy that took place in Middle-earth in the Second and Third Ages.

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Viewers always know that one of the characters featured in the first season of LotR: Rings of Power was going to be Sauron but the writers kept his identity a secret until the last few hours, literally. Unlike his master, Morgoth, Sauron's brilliance was in his long-term plans and guile as opposed to using force. He took on several disguises and identities over the years and fooled almost everyone in Middle-earth sooner or later.

9 Mairon The Admirable

rings-of-power-valinor-trees Cropped

Not a disguise, but his first and truest form, and one that he would recall later when trying to negotiate and manipulate. When the Valar and their servants, the Maiar, lived in peace with the Elves in Valinor, the being that came to be known as the Dark Lord Sauron was a force for beauty and good.

He was called Mairon, the Admirable, and he was one of the most talented and loved of all the Maiar. As the years passed, however, he was drawn to Melkor's side by the promise of knowledge, power, and wealth. When Melkor destroyed the Trees and stole the Silmarils, he was renamed Morgoth, and his servant Mairon followed him to Middle-earth.

8 Sauron, A Servant Of Morgoth

Finrod and the elves battle against Morgoth's orcs

After leaving Valinor, Morgoth and his forces settled in Middle-earth, and now with three Silmarils in their possession, few could challenge their power. Galadriel's brother Finrod died in the dungeons trying to get one of them back. He was ultimately successful, and although the details vary between the books and the show, Morgoth was defeated and his servant Sauron ran for the hills.

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It was during this long exile that Sauron took on other guises, or sometimes didn't, as his power and prestige as a Maia was enough to welcome him to any home or kingdom. With Morgoth now gone forever, Sauron wasn't seen as a threat anyway.

7 Thu The Huntsman

Sauron, Huan, and Luthien in The Silmarillion

Early versions of Morgoth's dungeon didn't include werewolves but instead were populated by a race of giant cats. These cats commanded the everyday workings of the castle above, which included minding the doors, running the kitchen, and interring prisoners.

Their master was Thu the Huntsman, and he commanded a whole host of wild and malicious beasts to serve Morgoth. This is an incarnation of Sauron that only appears in early versions of Beren and Luthien and hasn't made it into any on-screen adaptations. Rings of Power contains a few tasty nuggets of book lore, so depending on where Sauron goes next, Thu might appear in the future.

6 Annatar, Lord of Gifts

split image members of Galadriel's family Celembribor Elros and Elrond Galadriel in armor

The War of Wrath was still fresh in the minds of the Elves, and the name of Sauron had too much baggage, so when he appeared in Eregion he took on another disguise. The best way to get people on one's side is to give them free stuff, and that's exactly what Annatar did, hence the title.

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The gifts he gave were knowledge and art, two things that Elves love, so he met very little resistance. Although some saw through his promises, he fooled enough of the Elves that they helped him to make the Seven Rings of the Dwarf-lords and the Nine Rings of Men.

5 Halbrand, King Of The Southlands

Halbrand in The Lord of the Rings: The Rings of Power

To be fair, he never claimed to be this person. An overly-enthusiastic Galadriel pinned this identity on him while looking for an excuse to go back to Middle-earth and he let her do so, but it is worth noting that he initially wanted to stay in Numenor.

The character of Halbrand is an identity that's unique to the Rings of Power series, and although the lore does mention where Sauron appeared in the Second Age, it doesn't reveal everything. Between making the rings in Eregion or manipulating the Emporer in Numenor, he might have visited any number of locations.

4 The High Priest of Melkor

Rings of Power Ep 3 arrival in Numenor

Sauron knew that he would never be able to muster the forces needed to invade Numenor, so he came up with another brilliant plan. He surrendered and was brought to Numenor willingly as a hostage. In hindsight, he successfully invaded the kingdom, although it took a few generations for his machinations to start working.

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During his time here, Sauron introduced the Cult of Melkor and built a temple for his master. It might have been during this time that he gifted the rings of Men to certain Numeroean rulers. The powerful Men of the island kingdom were confident that their will was more powerful than that of Sauron, one of the Maiar, and their arrogance would be their undoing.

3 The Lord Of The Ring

Sauron in The Lord of the Rings: Fellowship of the Ring

Sauron's final incarnation is the one most viewers recognize because it was featured in a dramatic introduction scene in The Fellowship of the Ring. Being one of the Maiar, Sauron survived the destruction of Numenor but lost the ability to take any form he wanted.

Part of what helped to restore him was the power of the One Ring, although his form now was a reflection of that same terror and evil that had made them. When Isildur cut the One Ring from Sauron's hand, this form was destroyed, and it took hundreds of years for Sauron to assume another physical form.

2 The Necromancer

Necromancer The Hobbit

He's mentioned in The Hobbit but takes a much more central role in the movie version. It seems that Tolkien was unsure at first as to the identity of this character, but the Necromancer is an early version of Sauron.

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The incarnations of him that appear in the Third Age are some first attempts at a corporeal form after existing as little more than a malevolent evil spirit for centuries after losing the One Ring. This is one example, and it connects to some of Bilbo's adventures in the Hobbit in places like Mirkwood and of course, the Lonely Mountain.

1 The Eye

the eye of sauron and mount doom in mordor

As Saruman explained in The Fellowship of the Ring, Sauron was unable to take physical form, but he did exist as an entity in the Dark Tower overlooking Mount Doom. When Sauron appeared in the Palantir, or when Frodo put on the ring, this is how he looked, as a giant flaming eye.

This is an image created for the movies, but it makes sense to illustrate the point that Sauron isn't a mortal or even a Wizard. When the One Ring is destroyed, the tower and the Eye fell with it.

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