The universe exists in a state of balance. For every act of kindness, there's an act of selfishness to counteract it. In the Star Wars universe, there are the Jedi who are tasked with protecting the galaxy. Then there are the Sith, who take it upon themselves to conquer the galaxy and rid the world of the Jedi. This setting has given rise to numerous conflicts, films, books, video games, and TV shows.
The villains of the galaxy, the Sith Lords, have a very interesting history. They were once an entire society who had their own planet, using the Dark Side of the Force to create and foster a Sith army to conquer the galaxy. However, they were constantly killing each other for power, so the Rule of Two was established. Since then, there have only been two Sith Lords to work toward the end of the Jedi. In the time that the Sith established their new order, several of them rose through the ranks to become legendary. Whether through insane Force powers or through a specific action, they were feared above the rest of the Sith. These OP Sith were the scourges of the galaxy, and we'll be ranking 15 of the strongest.
15 DARTH MAUL
Darth Maul is canonically the first Sith to appear in a movie. While he didn't get a lot of time to shine in The Phantom Menace apart from the lightsaber duel at the end, there's much more to him than meets the eye. He was raised on a brutal planet where magic and combat were commonplace. Having a connection to the Force, he was one of the best fighters on the planet. When the Emperor trained him, he became even better.
Darth Maul has since been regarded as one of the best lightsaber duelists in history. Unfortunately, he was a character persuaded by emotion and revenge, which was ultimately his downfall at the hands of Obi-Wan Kenobi. All it took was someone to see through his strength.
14 DARTH TYRANUS
Dooku was once a Jedi who quickly became one of the best. He was easily the best lightsaber instructor in the entire Jedi Temple, and the rest of the Order knew it. However, some sketchy situations caused Dooku to feel a little disillusioned with the Jedi. Due to his connections and battle experience on top of that, he was a prime target for Darth Sidious.
After being brought over to the Dark Side, Dooku took the name of Darth Tyranus and was a powerful villain. He could duel multiple Jedi at a time without breaking a sweat and even fought against Yoda and lived. Tyranus also had access to several impressive powers, including the Emperor's trademark Force Lightning, which was already difficult to conjure in the first place.
13 DARTH MALAK
A noble Jedi by the name of Alek, it wasn't long before he was captured during a mission to investigate the villains of the galaxy. While captured, he was tortured and corrupted by the Dark Side of the Force. By the time the bad guys were done with him, Alek was no more and was instead crowned as the Sith Lord known as Darth Malak.
Starting out as an apprentice, his master was taken away and he became the Master. Taking multiple apprentices during his reign, Malak sought to create a Sith Empire. Malak had a masterful control over the Force. He could choke multiple opponents at a time and still throw his lightsaber. His most notable ability was being able to conjure a storm of Force energy that would incapacitate anyone who got caught in it.
12 DARTH REVAN
Every excellent Sith Lord had a master, and that was exactly the case with Darth Malak. When he was captured and brought over to the Dark Side, he wasn't alone. His Jedi friend, Revan, was captured as well. Both of them were turned to the Dark Side, but Revan was the one who took the role of Sith Master.
Even as a Jedi, Revan was regarded as the greatest champion that the galaxy had ever seen. When he became a Sith Lord, he was even stronger. Having a greater understanding of both the Dark and Light Sides of the Force, Revan was capable to unleash the Force in its purest form. Some regarded looking at Revan like staring into the very heart of the Force.
11 DARTH VADER
The story of Anakin Skywalker is always a tragic one. After having hopes of leaving the life of a slave to become a Jedi, it wasn't long before his unbridled power got the best of him. Through some temptation by Darth Sidious, Anakin managed to fall to the Dark Side and become the legendary villain known as Darth Vader.
Where the Jedi instructed Anakin to show restraint, he had none as Vader. Fully embracing his skills, Vader was one of the most powerful Sith known to history. His control over the Force was terrifying, to the point where he could pull down an entire Star Destroyer. He was also an expert duelist, being the primary force who hunted down any Jedi that survived Order 66. There were no Sith quite like Darth Vader.
10 DARTH KRAYT
A'Sharad Hett was once a great Jedi. However, his life was forever changed when the Emperor issued Order 66. After escaping by the skin of his teeth, Hett returned to his home of Tatooine and rejoined his life as a Tusken Raider. He became its leader and even came in contact with Obi-Wan Kenobi. After being defeated in battle, the Raiders abandoned Hett, who then went on a journey of self-discovery.
When all was said and done, Hett came out a Dark Lord of the Sith known as Darth Krayt. He was a terrible and swift force, having the size and strength to literally crush anyone that tried to oppose him. His command over Force Lightning was also strong enough that he could destroy massive stone structures with a single thought.
9 DARTH BANE
There's strength in numbers but, in Star Wars, strength seems to be lost. The massive Jedi Order wasn't able to detect it when Senator Palpatine infiltrated the Senate. Likewise, the Sith were once great in number, but lost a lot of what made them potent in the first place. This is where Darth Bane enters the picture.
He was part of a Sith Order that was massive and full of many soldiers. However, they lost a lot of their old ways that made them Sith in the beginning. Because of this, Bane thought it best to embrace the true power of the Dark Side. He unlocked several Force abilities that were unheard of at the time, including massive Force waves. He also had special armor that could deflect the blow of a lightsaber. He single-handedly rose above the ranks of the Sith and restructured the Order by creating the Rule of Two.
8 DARTH PLAGUEIS
Force abilities either make or break a Sith Lord, and it was an aspect of life that Darth Plagueis was especially interested in. While his apprentice was more focused on power and conquering, Plagueis wanted to have mastery over the Force, taking the time to meditate and study it. His crowning jewel has learning how to create life solely through the use of the Force.
Plagueis was also no slouch in combat either, using both his saber skills and the Force to easily subdue his opponents. However, he would never be able to unlock immortality because that ability exists only on the Light Side of the Force. Despite this, Plagueis had many impressive feats in his life, including creating Anakin Skywalker in the womb of his mother.
7 DARTH SIDIOUS
If there's one Sith Lord who can outdo creating life, it would be Darth Sidious. Being the apprentice of Darth Plagueis, he was taught the value of mastering the Force above all else. However, Sidious wanted more in life and had plans of conquering the galaxy to reshape it. Yet, he chose not to do so through brute Force or an invasion, but rather a more secretive and gradual infiltration.
Sidious easily deserves to be on this list as he was one responsible for the destruction of the Jedi Order and Republic in one fell swoop. He then created the Galactic Empire in its wake. Many tried to duel Sidious to take him down, but he was no slouch either. Spending years preparing, Sidious was able to take down multiple Jedi at once and was nearly unbeatable until the day he died.
6 DARTH TRAYA
Every Sith or Jedi takes their stance on life. They choose one side or another, ready to die for it. That was not the case with Darth Traya, who was a Sith Lord that somehow managed to find the middle ground between Light and Dark. She saw the shortcomings of the Jedi and the Sith, and sought to better the both of them to become something truly memorable.
Having this sort of raw connection to the Force allowed her to do incredible feats. Her trademark ability was being able to telekinetically control multiple lightsabers at once, being able to duel multiple foes without ever moving her body. She was skilled in all sides of the Force, and was a foe nearly impossible to take down. She could even sever an individual's connection to the Force.
5 DARTH NIHILUS
Some people fall so far into the pit of madness that, when they come out, it's impossible to recognize them. That was precisely the case of Darth Nihilus, the most vorcaious Sith Lord in history. He was a Force vampire of sorts; he would suck the Force Energy out of anything to feed himself and become stronger.
Darth Nihilus had such a strong connection to the Dark Side that even his very voice would cause immense pain to all who heard it. Nihilus was capable of draining entire planets of their connection to the Force, putting the whole galaxy at risk as long as he was alive. His only weakness is that he had to feed or he would slowly fade away. In his final moments, he became driven by his appetite, which became his downfall.
4 EXAR KUN
Exar Kun was once a powerful Jedi who was regarded as the most powerful duelist in the Order. It's easy to imagine the fear that the Order felt when he defected to the Dark Side. As a self-proclaimed Dark Lord of the Sith, Exar Kun posed a threat like no other. He began an entire war against the Jedi and used every ounce of his Force knowledge to gain the upper hand.
Exar Kun was a dueling master and could cut down any Jedi. As a Force user, while he had no more connection to Light Side abilities, he was an expert at Sith Alchemy. Through this, he crafted horrifying monsters to use in his army. At the end of his life, he also discovered a power that allowed him to separate himself from his body just before he died -- though it cost many innocent lives.
3 DARTH MALGUS
Darth Vader was a powerful Sith Lord, but even he had those that inspired him. The main Sith Lord that Vader respected from history from Darth Malgus. If we could describe Malgus in one phrase, it would be a combination of Sidious and Vader. Malgus was such an impressive dueler that he didn't even need to use the Force to win battles.
However, his connection to the Dark Side was nothing to sneeze at. His Force Lightning could kill multiple Jedi at once, and he later perfected this ability to conjure up extremely violent Force maelstroms. He was a primary figure who took down Coruscant back in the days of the Old Republic and would leave a large footprint on the Sith that preceded him.
2 DARTH VITIATE
We all know Darth Sidious as the Galactic Emperor, but even he has those who could best him. Several years in the past was a Sith Lord known as Darth Vitiate, otherwise known as the Sith Emperor. After being bestowed the title of Sith Lord by a legendary Sith Master, Vitiate took it has divine right to rule and sought to purge the galaxy of all hope.
His dueling skills were unparalleled, and many regarded him as one of the most powerful Sith Lords in existence. He was so strong in the Force that he could break someone's neck and choke them without moving a single muscle. He destroyed many planets and ruled with an iron fist. He garnered the respect of many people in the galaxy and would be forever remembered in history.
1 MARKA RAGNOS
Most Sith Lords were once Jedi and are slowly turned to the Dark Side. However, Marka Ragnos was born into it. Being the son of a Sith Lord, he had a connection to the Dark Side from birth, and was stronger for it. Many described him as the manifestation of the Dark Side of the Force, as he was one of the strongest Force users to have ever lived in the galaxy.
Marka Ragnos didn't even use a lightsaber. Instead, he imbued a sword with Sith magic to create a Sith sword. Ragnos's strength caused the Sith Order to enter what's known as the Golden Age of the Sith. That's all without recounting his various Force abilities. Marka Ragnos was so strong in the Force that he could even use it to make him invincible when he dueled.