Feanor and Fingolfin could definitely kill him. Feanor might even be able to destroy the One Ring as his skill in craft was much greater than Sauron or any other Elf that created the rings.
Characters who can easily defeat Sauron are; his Creator Eru Ilúvatar, his old master Melkor, and the Valar. Others who could overcome him would be Ungoliant who physically dwarfed Morgoth, and some great Maiar of Valinor described as almost as great in power as the Valar themselves.
Sauron's deepest fear was that Aragorn would use the Ring against him. With its powers of domination, Aragorn could comfortably take over the entirety of Sauron's dark army. Though this would eventually corrupt Aragorn, it would allow him to destroy Sauron and take his place.
In The Lord of the Rings, it is said that had Galadriel chosen to use her powers for evil instead of good, she would have been even more destructive and terrifying than Sauron himself. Galadriel was the greatest and most powerful of all Elves in Middle Earth in the Third Age.
Sauron feared her
The author said that she was the “last remaining of the Great among the High Elves” in the Third Age, and consequently was the one person Sauron must have feared most among all his enemies in the War of the Ring.
God is the most powerful entity in Tolkien's Lord of the Rings universe. The Elvish name for him is actually Eru Ilúvatar, meaning “the one, father of all.” So the question becomes: Who is the second-most powerful being? Originally, it was Melkor, “he who arises in might,” the most powerful of the Ainur (or angels).
Some of his powers include: pretty much whatever one can imagine. Most of Sauron's powers are left to the imagination, with only a few ever being fully revealed, such as his ability to disguise himself, his mastery of deception, control over fire, and the manipulation of the physical world around him.
Why did the elven kingdoms resist Sauron at the end of the Third Age? They knew that if the one ring was destroyed, their kingdoms would fade and they would have to leave. If the one ring wasn't destroyed, Sauron would destroy their kingdoms and they would have to leave (if they wanted to live).
While incredibly intelligent and powerful, Sauron's greatest weakness was his arrogance. He constantly underestimated the power of his enemies, which often led to his plans being thwarted and his armies defeated.
So, while Sauron was evil, Morgoth was clearly much worse.
All other men in the trilogy, even the underestimated and underappreciated Faramir, and his mighty brother Boromir, fall short of Aragorn's heroism. That is why Aragorn is the only one who could challenge Sauron in the Palantir, and win.
Sauron was known to be one of the most powerful of his order, and although Gandalf (known as Olorin in those days) was of the same order he was a less powerful being than Sauron.
However, in the Return of the King, Gandalf explains that when the One Ring is vanquished, Sauron will be "maimed forever, becoming a mere spirit of Malice that gnaws itself in the shadows, but cannot again grow or take shape.
In theory, yes. It would be possible for him to control them using the ultimate ring of power, in the same way that an alpha wolf controls its pack.
The Third Age is the time period in which The Hobbit and The Lord of the Rings are set. This age is marked by the rise of Sauron against the Númenórean kingdoms and his eventual defeat during the War of the Ring. The Fourth Age is the time period after the fall of Sauron, when Dwarves, Men, and Hobbits prosper.
He was only worried about finding the Ring, and he already had plenty of servants to do that for him. So, in short, the power that Sauron would have gained by recruiting the Balrog wasn't worth his time.
Conclusion: the drakes of the last days of the third age were probably too weak, too far away and simply too uncontrollable to be of any use.
But when it becomes clear to Galadriel that Halbrand/Sauron cannot tell the difference between “saving” and “ruling” Middle-earth, she rejects his proposal.
Gandalf, like all the five wizards of Middle-earth, was a Maia, an angelic spirit of the same order as Sauron.
While the previous 19 rings were crafted with the help of the Elves, the final ring, the 'One Ring to rule them all,' was crafted by Sauron alone; with the ability to dominate the other rings, the One Ring was made with some of Sauron's own power, in order to make it more powerful.
Many Lord of the Rings fans also say Tom Bombadil is actually the most powerful character in all of Middle Earth, due to his apparent immortality, ability to completely resist the Ring, power over his domain, and knowledge that comes from living since the beginning of time.
Sauron. The Dark Lord Sauron is the most powerful villain in Middle-earth. He is a Maia, one of the divine spirits who entered the world to aid the Valar in their work. Sauron is responsible for creating the One Ring, which grants him immense power and the ability to control others.
Galadriel has very strong magical powers, and she is said to be the greatest of the Ñoldor after Fëanor. The majority of her powers come from her Ring of Power, Nenya, the Ring of Water.
Uruk-Hai. Lurtz was the first and one of the strongest orcs known as the Uruk-Hai that were created by Saruman the White. He led a party of Uruk-Hai to Amon Hen, where they intercepted the Fellowship of the Ring and tried to capture Frodo.