While the fight between Vader and Sauron would seem promising, it would ultimately end in Darth Vader's defeat. Though Vader was strong in the ways of the Force and exceedingly handy with a lightsaber, he'd be facing a primordial being whose very powers helped shape the foundation of the world.
In Star Wars Legends and Canon, Galen Marek (Starkiller) is the only Jedi (other than Obi-Wan Kenobi) to put a beat down on Darth Vader/Anakin Skywalker.
Sauron wins. Easily. Originally Answered: If Voldemort, Sauron, and Darth Vader we're locked in a cage match - who would win?
Luke Skywalker
However, once Luke fully embraced his power in Star Wars: Return of the Jedi, he proved that he was indeed stronger than Darth Vader and struck his father down.
Sauron may technically have more power and longevity behind him, surviving not one but two massive defeats. In this respect, Palpatine has something Sauron does not have: success.
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.
Post Fight
Another thing to mention is that Sauron has bested multiple wizards before like Saruman or Gandalf, meaning that he'd eventually beat Voldemort in the end, though the Avada Kedabra could most definitely kill him. Boomstick: If you think Voldemort stood a chance, you'd be Saurong. Wiz: The winner is Sauron.
1 Darth Sidious
There has been no Sith, as powerful, meticulous, nor as evil as the Emperor himself, Darth Sidious. As previously mentioned, Sidious trained in the Dark Side by Darth Plagueis before Sidious killed Plagueis in his sleep, making Sidious a Sith Master.
Introduced in the first film in the original Star Wars trilogy, Governor Tarkin is the Grand Moff of the Galactic Empire and commander of the Death Star.
Vader used his pain and anger to fuel his Dark Side powers, becoming one of the most powerful Sith ever and perhaps the most feared. He was the enforcer of the Empire, using his red lightsaber and black armor to strike fear into his enemies, becoming an instrument of terror to fight the Rebels.
His most prominent role was that of Admiral Motti, the arrogant, mocking Imperial officer who is choked by Darth Vader in Star Wars (1977), after Vader finds his "lack of faith disturbing".
Darth Vader saved Luke at the end of 'The Return of the Jedi' because of the inner conflict that he never fully forswore. Darth Vader's torn persona finds its roots in the Jedi and the man he used to be – Anakin Skywalker.
Isildur took up the hilt-shard of Narsil and cut the One Ring from Sauron's hand, vanquishing Sauron.
Most specifically though, Vader hated the most important person in his life, his son Luke Skywalker. Vader believed that Luke was the only thing standing between him and ultimate power. So, in short, the person Darth Vader hated the most was his own son- Luke Skywalker.
Darth Vader's Insecurities are His Biggest Weaknesses
In the end, virtually all who have made the attempt to use Vader's cybernetic nature against him have ended up dead or defeated. The elite few who have had the upper hand, even before his conversion to mechanical monstrosity, have done so by dominating him mentally.
In the process, the Emperor enhanced his apprentice's abilities as he earned back his spot in the Empire. Growing in his power, Vader's confidence that he can kill his master gives him a new perspective. “You can destroy the Emperor.
As Supreme Commander, Darth Vader was the ranking leader of the Imperial Military.
Although Tarkin didn't believe in the Force, he respected Vader a lot, as he was the Emperor's enforcer, and he even grew to admire Vader's way of inducing fear within others.
Thanos wields more power and authority than Darth Vader, existing as a stronger and more capable villain overall.
Master Yoda has risen above all others to claim the top spot as the most powerful Jedi of all time and the true chosen one according to IGN's audience. He won pretty handily as well, as he was victorious in 89,756 of his 95,243 battles and had a win percentage of 94.2%.
According to Star Wars Legends content, the first Sith was a former Jedi Master, Ajunta Pall, who became a so-called Dark Jedi, or “Fallen” Jedi. As the name implies, these Force-sensitives chose to practice the Dark Side, and rejected the Light Side of the Force.
A Sith Lord with the ability to cheat death and create life, Plagueis is the mentor of Sheev Palpatine / Darth Sidious, who, in accordance to the Sith's Rule of Two, eventually betrays Plagueis by murdering him in his sleep, taking his place as Sith Master.
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.
Adar talks about Sauron's experimentation with his orcs in his quest for power and then reveals how the mistreatment of his children led him to split Sauron open, killing him to save the rest of the Uruk.
Both Morgoth and Sauron managed to inflict significant damage upon the world and their enemies before their downfall, but Morgoth was undoubtedly the more powerful of the two.