The main bad guy in The Lord of the Rings: The Rings of Power is Sauron, the dark lord and primary antagonist of Middle-earth, who orchestrates events from the shadows, appearing in disguise (like as Halbrand or the 'Lord of Gifts' Annatar) to manipulate elves and men into forging the Rings of Power, with his larger goal being the domination of Middle-earth. While characters like Adar served as immediate threats in Season 1, Sauron is the overarching evil masterminding the series' conflicts.
Sauron is the primary antagonist, through the forging of the One Ring, of J. R. R. Tolkien's The Lord of the Rings, where he rules the land of Mordor and has the ambition of ruling the whole of Middle-earth., He is also identified as the "Necromancer" of Tolkien's earlier novel The Hobbit.
Is the Necromancer actually Sauron? Yes, the Necromancer in Dol Guldur is Sauron. He disguised himself as the Necromancer so that he might build up his forces and power and once again try to overtake Middle Earth. He needed to hide his identity from the Elves as long as possible to gather his power.
Sauron was originally a Maia, a powerful spiritual being, who served the dark Vala Morgoth during the First Age. After Morgoth's defeat, Sauron became the primary antagonist of the Second and Third Ages, forging the One Ring to control the other Rings of Power and dominate Middle- earth.
Sauron is the main antagonist of the 2022 Amazon Prime Video's fantasy series The Lord of the Rings: The Rings of Power, which is based on J.R.R. Tolkien's Middle-earth legendarium. He is a fallen Maia that became a devoted servant of Morgoth.
Sauron's rise to power in the Second Age is portrayed in the Amazon prequel series The Lord of the Rings: The Rings of Power. He first appears disguised as the non-canonical human character Halbrand, and then in the second season as Annatar (a canonical alias of Sauron), both played by Charlie Vickers.
Galadriel was never evil. Certainly she was never an ally of Morgoth or Sauron. For most of the Third Age at at least half of the Second Age she did a great deal to protect and defend Lothlorien, and keep its people safe from forces of evil, including orcs. In her youth she was a rival to Fёanor.
while Sauron was more powerful than Gandalf in a direct comparison, their roles and methods were fundamentally different. Gandalf's strength was in enabling others to resist evil, while Sauron sought to dominate and enslave.
The Dark Lord unveiled himself in dramatic fashion in the Season 1 finale of The Lord of the Rings: The Rings of Power, which reveals that Middle-earth's Big Bad has been disguising himself as none other than Halbrand (Charlie Vickers) this whole time.
His task was to do the bidding of his masters and so when he proved unfaithful in doing that task his masters stripped him of his robes and gave them to one who would do their bidding. Gandalf is now the White, Saruman as he should have been.
But that's actually the answer: Eru Said So . The Undying Lands are a place for immortal beings (Eldar), and mortals are forbidden from entering.
His two most salient powers were his knowledge and his voice. Saruman was, in a very real way, the junior brother of Sauron both having been Maia of Aulë, Valar of Smithcraft, in the very beginnings of time.
Who did Sauron disguise himself as? In the Second Age, Sauron frequently disguised in "a fair form", and took the false identity of Annatar, "Lord of gifts", among the Elves and in the kingdom of Númenor, which he intended & succeeded to destroy from within.
Sauron is, in fact, much stronger than Gandalf or Saruman.
The Nazgûl (Black Speech for "Ringwraiths"), also known as the Nine Riders or Black Riders (or simply the Nine), were Sauron's "most terrible servants" in Middle-earth. They were mortal Men who had been turned into wraiths by their Nine Rings of power.
Sauron was originally a Maia of Aulë the Smith; his name then was Mairon, meaning "the admirable." He learned much from Aulë in the ways of forging and crafting, becoming a great craftsman, and mighty in the lore of Aulë's people.
At the end of the second age, the High King of the Elves, Gil-galad and Elendil, the King of the Numenorians in Gondor, defeated Sauron in armed combat,  although they both died in the fight. There is a long history of Elves or extremely powerful men defeating Miar - like the Balrogs.
Elrond chose the fate of the Elves and therefore the choice was presented to his children. The reason why Eldarion and his sisters (the children of Aragorn and Arwen) were born mortal was because Arwen chose mortality and therefore that fate was passed on to the rest of their line.
As a Maia, Gandalf was an angelic being in human form, in service to the Creator (Eru Ilúvatar) and the Creator's 'Secret Fire'. He took on the specific form of an old man as a sign of his humility. His role was to advise but never to attempt to match Sauron's strength.
He did not trust Gollum, for he divined something indomitable in him, which could not be overcome, even by the Shadow of Fear, except by destroying him.
The Ring's effects
Inversely, the hobbits' good-naturedness and lack of ambition makes them less susceptible to the Ring's promises of power, as in Frodo and Samwise Gamgee, who are able to handle the Ring for extended periods of time.
SAURON. He is the lord of the rings. And the title is him also. The most mysterious character yet the title is him.