While Darth Sidious (Emperor Palpatine) is widely considered the most cunning and successful Sith Lord, often cited as the epitome of pure evil for his grand manipulation of the galaxy, others like Darth Vitiate (The Sith Emperor) from The Old Republic era in Legends often compete for the title of "most sadistic" due to his vast atrocities, including mass sacrifices and attempts to consume entire worlds, making him a strong contender for sheer cruelty and scale of suffering.
Darth Sidious, also known as the Emperor and Supreme Chancellor Palpatine, is not just the evilest Sith in Star Wars (arguably in both canon and Legends) but the evilest villain overall, deemed so thanks to his irredeemable actions throughout the Skywalker saga and surrounding content.
Darth Vectivus. He basically got all the power he wanted and then retired to live with his family and friends and died peacefully, none of the Sith backstabbing. Vergere is potentially another (although I'm still pissed at the retcon of her being Sith).
Overall Winner: Darth Revan
Revan was the better duelist, the smarter tactician, and the more well-rounded Force user. Nihilus was terrifying, but his lack of control and battle skills made him vulnerable to an opponent who could think ahead and counter his attacks.
Baras gained a great deal of weight -- becoming one of the fattest Sith Lords -- lost his hair, and took to wearing a mask. His dark side degradation and aging led to his skin becoming pallid and wrinkled, his eyes also changed color from a dark brown to red.
Darth Maul is the weakest. Bane was strong : he killed all the Sith and lots of Jedi.
Several Hutts known for being crime lords who lived opulent lives overseeing criminal underworld activities like spice smuggling, slavery, gambling, and bounty hunting in Hutt Space. They were typically obese, with the muscular Nar Shaddaa kingpin Grakkus being an exception.
Yoda will absolutely have studied and come across Force Wounds and Nihilus' enhanced drain, and likely has the aforementioned knowledge and raw power to counter it. Nihilus is a one trick pony. That trick is a nuclear bomb, yes, but if you counter it, that's all he's got. Yoda wins.
No, Darth Plagueis is not Anakin Skywalker's father; Anakin had no biological father, being born of the Force itself in response to Plagueis's dark side manipulations, with Palpatine's tales of Plagueis's power over life being a manipulation to turn Anakin to the dark side, though Plagueis's attempts to create life did inadvertently cause Anakin's conception.
In canon it was Kirak Infil'a , Cere Junda, Obi-Wan and Lord Momin . All messed him up quite badly with Kirak winning round 1 but losing round 2 and Momin cutting off his arm. Obi-Wan actually beat Vader. In Legends it was Shaa Koon, An'ya Kuro, a clone of Maul and Galen Marek.
"Darth Plagueis was a Dark Lord of the Sith, so powerful and so wise, he could use the Force to influence the midi-chlorians to create life. He had such a knowledge of the dark side, he could even keep the ones he cared about from dying."
It's Legends now, but there was one benevolent Sith. His name was Darth Vectivus. He was the boss of a mining colony and basically made it into a powerhouse using Dark Side power. He died surrounded by his loved ones and family.
Chastened by his former Master on the principle of the Rule of Two, Maul abandoned his claim to the mantle of the Sith, focusing instead on building an empire of his own—the Crimson Dawn—by controlling the criminal underworld.
Top 30 of the most evil villains ever
Qimir has already been calling himself Darth Venamis, and is ready to officially be a Sith Lord Apprentice, but, is also already conspiring to get a pupil of his own, & eventually kill his own master as well.
Matthew J Meyer George Lucas has stated: "Anakin Skywalker was conceived by the midi-chlorians, but it was Palpatine who manipulated the midi-chlorians to create Anakin" (Source: "Star Wars: Episode III - Revenge of the Sith" DVD commentary, 2005).
It kicks off right after the end scene of ROTS and shows Vader beginning his hunt for Jedi in his new body. His very first target is a Jedi Kirak Infil'a, a Jedi who lived for combat who nearly kills Vader.
Vader and Revan were both immune to drain, but for what reason? Was it the armor? Or something else?
Darth Maul has the edge in a fight without using the force. Vader is powerful, but without the force, he's slower and bound by armor, making him less agile. Anakin Skywalker (before his duel with Obi-Won) would probably beat Maul though. Maul is sharp, brutal, and precise.
In Legends, probably the most unusual species to join the Jedi were the Iron Knights - a silicon based species that looked like shards of crystal. To function in galactic society and as Jedi, they used modified droids to serve as humanoid bodies.
The memoirs of Boba Fett mention that Jabba "was known as a cruel, depraved, sadistic ruler" with a "penchant for violent entertainment, torture," and that he possessed "vicious temper, gruesome appetite, and endless greed." According to Fett's memoirs, Jabba keep "scantily clad slave girls chained to his throne for ...
After Jabba's death, Fortuna gained control of Jabba's palace and amassed servants and slaves of his own, becoming a crime lord. Over time, he grew obese. Years into Fortuna's reign, after the second rescue of Grogu, Boba Fett and Fennec Shand arrived at the palace, killed Fortuna's guards and released a slave.