10 - Darth Vader

Midi chlorian measures the potential of a Force Sentient, and Anakin Skywalker was the Jedi with the highest midi-chlorian levels of all time. However, he never reached his full potential, leaving him in 10th place.

Anakin thought it was only to save his wife's life to join the dark side. He was carrying a profound anger and sense of loss inside of his heart-led to his fall.

Apprentice to Darth Sidious,  then known as Senator Palpatine, became Darth Vader and killed all the Jedi in the Jedi Temple. Obi-Wan Kenobi, his former Jedi Master, dueled him in Mustafar and won, leaving Father to die in a lava bath.

Darth Sidious saved Father and locked him in the iconic life-sustaining dark suit for the rest of his life. However, his duel with Obi-Wan Kenobi was his downfall, as his injuries prevented him from reaching his full potential.

Though he never became as powerful as he could, Darth Vader served under his lord and became the ultimate Jedi killer. He made it his personal mission to conduct the Great Jedi Purge.

During this time, true to the Law of Two, Father was already planning to overthrow Darth Sidious and become Sith Lord himself. He secretly trained an apprentice for when that day came. Sadly for him, the apprentice turned to the light side and was the one responsible for the start of the Galactic Civil War.

Father then started to train with Darth Sidious, and his greatest apprentice was the Sith Lady-to-Be Lumiya .

At the end of the Galactic Civil War, Luke surrendered to Father, who took him to the throne of the second Death Star. There, Darth Sidious made Luke duel his father, Father. Father lost, and Luke refused to kill him screaming, " I am a Jedi, like my father before me! " This made Father feel proud, and as Sidious attacked Luke with Force Lighting, Father killed his son's aggressor, fulfilling the prophecy that he was the chosen one to vanquish the Sith.

9 - Darth Bane

Darth Bane is the Sith Lord responsible for creating the Law of Two, a fact that highlights his importance.

He also marked his place in history when he created his own Sith Order. Bane was instructed in the old Sith Order by the Sith Council that existed back then, but he thought it was a weak council. So he studied Darth Revan's holocron, and, armed with his strength and new knowledge, he destroyed the old Sith Order in order to create his own.

When Bane was attempting to create his own holocron, Sith Lords, the Jedi sent a task force to kill him. Although outnumbered, the Sith Lord and his apprentice killed every single one of the Jedi attackers.

In his later life, Bane, began to worry that his apprentice, the female Sith Zannah, was too weak to overthrow him, as is needed in the Law of Two.He started looking for a new apprentice but it was not necessary, as Bane had underestimated Zannah. The apprentice is going to kill him in a lucky shot.

Years Later, Bane's Order overthrew the Republic.

8 - Freedon nadd

Freedon Nadd was a Sith Lord in a very ancient world. His era far precedes that of the previous Sith.

Though he was once a Jedi, he killed his master and fled to join the old Sith Order, under the apprenticeship of the Sith Lord Naga Sadow.

He was a sorcerer-like Sith who controlled the Force better than the lightsaber, and after he thought he had learned everything he could from Naga Sadow, he turned his master and became Dark Lord himself.

He ruled over Onderon all of his life. After his death, he was entombed there, and his tomb remained a powerful hotspot for Sith power.

A great deal of time later, King Ommin resurrected Freedon Nadd, and he took a new apprentice, one that was meant to be the greatest and strongest Sith Lord of all time.

7 - Ulic Qel-Droma

Ulic Qel-Droma was a Jedi on a mission, pretending to be a dark Jedi. However, he was injected by a rage-augmenting chemical that made him fall to the dark side.

He then went to meet Nadd's apprentice-that's right, the greatest Sith Lord who ever lived, whom I shall not name yet. The Lord, but Freedon Nadd's spirit interrupted and declared them both Sith Lords. They then proceeded to assault the Uile Qel-Droma coldly killed his Jedi brother.

Nomi Sunrider, one of the greatest Jedi ever, was so enraged by the fratricide that, through her power, she severed Ulic's connection with the Force.

He slowly became remorseful of his actions, and eventually led the Jedi and Republic forces to the stronghold of the greatest Sith Lord ever. Together, the Jedi and Republic killed the Sith Lord in an epic battle.

Ulic then exiled himself and took Nomi Sunrider's daughter as an apprentice.

6 - Marka Ragnos

Marka Ragnos was the best duelist of the entire Star Wars Saga.

If you love lightsaber combat, you will love Ragnos. He was famed as the best, and defeated any who opposed him in single combat. However, his control of the Force was not top notch.

Nevertheless he did another great job, Darth Vitiate, and he also came back as a spirit. In life, he reigned supreme and unchallenged for more than one hundred years.

His spirit wandered for millenniums, but eventually he got sealed off by a Jedi forever.

5 - Revan

Revan was a Jedi who wanted to protect the countless lives that were threatened by the Mandalorian invasions. However, the council refused to let him or any Jedi intervene in the war. So Revan, displaying the best diplomatic abilities and leadership virtues of all saga, mustered an enormous number of Jedi to go fight with him, disobeying the council. His padawan Malak followed him, and that group won the war for the Republic.

But they did not return. Instead, they found the Star Forge, an automated shipyard that allowed them to produce an immense fleet and give them power, which seduced them to become Sith. Darth Revan became the Lord of the Sith and Malak his apprentice.

Revan was also known as a really powerful Sith Lord, able to turn Jedi at will and gain allies from everywhere.

He was later captured by the Jedi and brainwashed to convert back to the light side. As a Jedi once more, the third most powerful Jedi ever, Revan defeated his apprentice, now Dark Lord Malak, and was declared the hero of the Republic.

4 - Darth Plagueis

He was the Sith's ultimate scholar. He was obsessed with tricking death and achieving immortality, and he conducted lots of experiments resulting in extensive knowledge. This knowledge made possible for future Sith, like his apprentice, to cheat death.

And who was his apprentice? Darth Sidious, the Sith you may know as Senator Palpatine. That's right, meet the master of Darth Vader's master.

He valued knowledge above all, and here is something he said to his apprentice Darth Sidious once:

If you do not already want to murder me, you will be before I'm through with you. The urge to kill one's superior is intrinsic to the nature of our enterprise. My unassailable strength gives rise to your envy; my wisdom fuels your desire; my achievements incite your craving. Thus it has been for one thousand years, and so it must endure until you have parity. Then, Sidious, we must do our best to sabotage the dynamic Darth Bane set in motion, because we will need each other if we are to achieve our ultimate goals. In the end, there can be no secrets between us; no jealousy or mistrust. From us, the future of the Sith will fountain ...

-Darth Plagueis to Darth Sidious

3 - Darth Vitiate

Darth Vitiate killed his father with only a thought at the age of 10. He later went on to kill off an entire planet, including numerous Sith Lords, and absorbed all of their power. In doing so, he became immortal-almost (he passed away milleniums after his birth). Vitiate was the Sith Lord who reigned the longest.  

He also once bested Revan and was Darth Plagueis's muse since Plagueis and his knowledge.

2 - Darth Sidious

Darth Sidious was an apprentice to Darth Plagueis.

He took the life of a politician as a door to his true intentions or taking over the galaxy. While still an apprentice, Sidious took an apprentice violating the rule of the two: Darth Maul.

He usurped the throne of Dark Lord of the Sith by killing Dark Plagueis in his sleep.

Later, Jedi Knight turned Anakin Skywalker into his apprentice: Darth Vader.

With Father, he purged all of the Jedi he found and took over the galaxy, forming the Galactic Empire.

He reigned supreme until he was killed by Father when he was trying to kill Luke with Force Lightning. However, he was so powerful, he did not stay dead. He was the body of his clone and was forced to change bodies often to stay alive. He managed to turn Luke Skywalker for a letter period of time.

One of his allies sabotaged his fresh supply of clones, and Sidious, with no body to occupy, desperately tried to take the body of Anakin Solo, Father's grandson and the son of Leia and Han Solo, but he did not succeed and finally perished .

1 - Exar Kun

Kun was a Jedi that wanted to become stronger and stronger. His desire for power was so strong that he left the order in pursuit or forbidden teachings. In the end, he achieved his goal by becoming the most powerful Sith of all time.

When Kun left the order, he entered the tomb or discussed Sith Lord Freedon Nadd. Freedon Nadd taught him everything he knew before getting killed. Exar Kun later traveled to Yavin 4, where he amassed even more power.

Can killed entire Sith Cults that were too powerful for his liking. The stole a very ancient Sith holochron, which he used to gain even more power. He used his power to turn many Jedi Padawans to the dark side and convince them to kill their masters.

Exar Kun later went and killed the supreme chancellor, and he dued the grand master of the Jedi Order, who was no match for him.

The foundations of a well-established Sith Empire were laid.

When he was attacked by the traitor Ulic Qel-Droma and his thousands of troops, he separated his body from his spirit. Nomi Sunrider and thousands of thousands of Jedi managed to incarcate Exar Kun in a temple forever.

Or not quite forever, as forever is a long time. When Luke was already the grand master of a new Jedi

Order, Killing one in the process. He separated Luke's body from soul but was defeated by the combined power of all or Luke's students.