From lightsaber might to Force abilities, Sith have multiple powerful ways to impose their evil in Star Wars.
Even in a project like Andor, where the central villain on screen isn't a Sith, they're still the mastermind behind everything, tirelessly ruling the galaxy from the shadows and bringing about a dark age in the galaxy. The canon is full of awesome Sith that are constantly being expanded upon and their powers are shown in astonishing displays.
Various Sith Lords display their power in various forms. From incredible Force feats to ferocious lightsaber slashes to sheer intelligence and influence, Sith have multiple ways to impose their evil in Star Wars.
10/10 Savage Opress
In many ways, Savage Opress is an underrated villain, and since Sidious and Dooku inherited the Sith Order's legacy during the Clone Wars, people don't immediately associate him with the Sith Lord . However, Opress is a Sith Lord for the time being, not someone who can be completely overthrown.
Under the tutelage and leadership of his brother Maul, Opress became a Sith apprentice for a short time and proved himself quite powerful through sheer raw strength and bestial tendencies. Although he doesn't have the skill, wisdom, training or experience to approach other Sith Canon, it's impressive that he managed to murder multiple Jedi in such a short amount of time.
9/10 Darth Momin
Originating from the awesome Darth Vader comics, Darth Momin isn't a name every Star Wars fan will be familiar with. While not as powerful as brute force, Momin impresses with his intelligence and unique skills.
Like many Sith Lords, Momin killed the master who trained him in lightsaber combat. However, it's not his swordsmanship that makes him such a menace. Momin manipulates the Force in unprecedented ways, such as creating weapons after his death and trapping his consciousness in his mask.
8/10 Darth Tenebrous
Not much is known about Darth Tenebrous in the Star Wars canon, but as the fabled Sith Master of Darth Plagueis and the underrated Sith Lord in the Legendary timeline, Bees People deserve it.
Tenebrous has almost everything. Not only is Tenebrous a skilled lightsaber duelist and master of various Forces, such as Force Speed, but he's also incredibly intelligent. He designed his starship and created a retrovirus, valued and thrived in science, all of which made He is a powerful hidden enemy.
7/10 Darth Maul
In his later years, feeling betrayed by his former master and seeing the entire Order as his enemy, Maul denounced the Sith, relinquished his title of "Darth" and became a shadow. For a long time, though, he was a powerful Sith Lord.
As Darth Sidious' apprentice and wreaking havoc alongside his brother, Maul proved himself to be one of the most powerful and important Sith in the entire canon. A vicious lightsaber duelist with underappreciated wits and skills with the Force, Maul is as elusive as an animal. Killing Qui-Gon Jinn wasn't easy. Despite the loss, his longevity and talent are a testament to his strength.
6/10 Count Dooku
Arguably Star Wars' most underrated villain is also one of its most powerful Sith Lords, Count Dooku, who is the focus of half of the Jedi lore. He's on par with the greatest lightsaber fights in the galaxy, but he's so much more than that.
Dooku is an intelligent man who is well versed in every aspect of how the galaxy works. He knows both the light side and the dark side of the Force like the back of his hand, and uses both advantages to defeat the likes of Obi-Wan Kenobi and Anakin Skywalker. As a lightsaber warrior, he's rivaled only by the greatest characters in Star Wars, and his legacy is only hampered by the fact that he's little more than Palpatine's pawn.
5/10 Darth Bane
The creation of the Rule of Two by Darth Bane is one of the most important events in galactic history, as he toppled the first domino, causing Sidious to strangle the galaxy. His power, especially in Legends, is immense.
Bane is known for his superb lightsaber skills and for intimidating his enemies. Combining these skills with his leadership and military strategy, Bane is a powerful Sith Lord in a variety of situations, from 1v1 fights to all-out combat. While his full powers and story have yet to be explored in canon, he's still a total badass.
4/10 Darth Plagueis
Darth Plagueis is more than just the subject of the stories told in the iconic meme scene. Instead, he was one of the greatest and most powerful Sith Lords who ever lived.
From his talent in science to his deep understanding of the Force to his teaching Sidious everything he knew, Plagueis doesn't need to slaughter Jedi with a lightsaber to prove his strength. Fans are looking forward to a more canonical look at the mind and workings of the fearsome and impressive Sith Lord.
3/10 Darth Revan
Darth Revan is possibly the greatest mystery in Star Wars, recently brought into canon by the Legendary. The character's potential, no matter which direction the canon chooses to go with them, is endless, and assuming they're anything like those in the Legends, they're some of the most powerful Star Wars characters ever.
Everything about the one-time Jedi Sith radiated power, from his mastery of the lightsaber to his vast knowledge of the Force to how easily he slaughtered all kinds of Sith/Dark Jedi/Jedi. Able to use both the dark and light sides of the Force in battle, Revan wields the Force in such an open and pure way that he is nearly impossible to defeat. Telepathy, force sensing, force lightning, lightsaber fighting, etc.; Revan is proficient in many aspects, and due to his lack of exploration of the canon, his status is second only to other Sith.
2/10 Darth Vader
One of the biggest "what-if" scenarios in Star Wars is what if Anakin Skywalker — Darth Vader or not — reaching his full Force potential? Even when he doesn't, though, Vader is one of the most powerful characters in Star Wars.
In many mediums, through his utter and merciless destruction of everyone in his path, through his daily struggles fueled by hatred, rage, and the dark side of the Force, Vader continually demonstrates His strength and mischief. He'd wipe out most other classic Sith Lords in battle, just as he'd wiped out various Jedi after his fall. Despite losing several midi-plasma, his mastery of the Force and ability to wield it with such force is second only to one.
1/10 Darth Sidious
Darth Sidious surpasses nearly all other Sith Lords and Star Wars villains in the legendary and canon timelines in terms of intelligence, lightsaber skills, understanding of the Force, and power in general.
The man who orchestrated the Clone Wars and subsequent destruction of the Jedi Order was not just a political genius with an affinity for the dark arts. Sidious is a lightsaber master and his kills on Maul and Kit et al show that fist. His knowledge of the dark side is unparalleled, and in terms of accomplishments, he is undoubtedly the greatest Sith of all time.