Sheev Palpatine, also known by his Sith name Darth Sidious, is a fictional character in the Star Wars franchise created by George Lucas.
Darth Sidious was always stronger than Vader, which is why he ruled over him for almost 20 years and turned him into the Sith Lord he was.
Vader held respect for Tarkin which is clearly shown and the only case in which Tarkin outranked Vader would be the case in which Vader was in the Death Star or within Tarkin's Oversector which he likely was as Tarkin was Grand Moff of the Outer Rim Oversector, the largest one.
Who had authority over Vader? The only one who really had authority over Darth Vader is Emperor Palpatine. Notice we never hear Vader being referred to as “General” or “Admiral” by anyone in the Empire, so he's basically outside the rank structure entirely. His only official purpose is to serve Palpatine…
He was an intelligent and cruel man, who served for a long time in the Army: he knew how much Vader was dangerous, but he also knew that he was the Emperor's mastiff. Knowing this, he knew that as long as he made his work and the emperor was happy with his work, he didn't need to be afraid of Vader.
His armor could be hacked and controlled by a device. In a turn of events, Darth Vader's right limb holding his dangerous scarlet lightsaber was moving of its own accord toward his neck. This was a dangerous weakness indeed.
During the Clone Wars, officers such as Captain Tarkin served under the Jedi Generals appointed to lead the Republic military. But Tarkin thought the Jedi's traditional role as peacekeepers made them a poor choice for prosecuting the war against the Separatists.
Because he was not an active member of the Jedi Order during Order 66, Infil'a escaped execution. Some time later, he faced the Sith Lord Darth Vader wielding a green lightsaber. Infil'a put up a fierce fight against Vader, almost killing him by throwing the Sith Lord off of a cliff.
Admiral Ozzel : [appearing onscreen with Captain Piett] Lord Vader, the fleet has moved out of lightspeed and we're preparing to... Darth Vader : You have failed me for the last time, Admiral! Captain Piett?
The Star Wars universe establishes Snoke as a Force-sensitive artificial being who was created by Emperor Palpatine, and used by him to reclaim control of the galaxy. As Palpatine's puppet ruler, Snoke manipulates Luke Skywalker's nephew, Ben Solo, to the dark side of the Force and serve the First Order as Kylo Ren.
Darth Vader was the stronger of the two by far, but in most cases with lightsaber duels, the victor is the one with the strongest connection to the Force. Obi-Wan finished his last fight with Vader by hurling a barrage of rocks, and it's unlikely he had lost this level of power by A New Hope.
As soon as Anakin Skywalker became Darth Vader, he already faced his most persistent nemesis and lost, namely his own master, Obi-Wan Kenobi.
The duel. Darth Vader defeats Darth Maul. The two Sith Lords engaged in a lightsaber duel, going through the volcano and onto a bridge situated over a river of lava, which collapsed, though they both survived and continued their battle.
Only one person could defeat Darth Vader once and for all. The spirit of Anakin Skywalker, long dormant, finally rose and overcame the dark side. While his body failed him, Anakin rose once again and defeated the Sith once and for all. Both Sidious and Vader met their ends that day, at the hands of Anakin Skywalker.
Darth Vader's Suit Embeds Needles In His Skin
Inside his suit and mask, Vader has a series of needles in his skin. Unfortunately, these needles, which transmit neurological data throughout his body and allow him to control his limbs, also cause him constant pain.
Visions of Obi-Wan. The comic opens during the last moments of Revenge of the Sith, recreating the well-memed instance when a despondent, freshly-armored Vader cries out with a drawling “nooooooo” over how much he's lost.
This information comes to light form the comic series Darth Vader: Dark Lord of the Sith by Charles Soule and Giuseppe Camuncoli, in particular issue #7. Palpatine admits to Darth Vader that the Jedi he actually feared most was none other than Jocasta Nu.
Did Darth Vader ever lost a fight? Darth Vader is one of the greatest villains of all time. But even he gets beaten sometimes. CBR lists all of the folks who managed this improbable feat!
Grand Master Yoda encountered the specter of Darth Bane during the Clone Wars. During the war, Jedi Grand Master Yoda ventured to Moraband on a journey to discover the secrets of immortality. He entered Bane's tomb and encountered a fiery vision of the ancient Dark Lord.
When Luke Skywalker fired the proton torpedo that destroyed the space station, Tarkin was killed in the explosion.
Post-Endor
One of the most powerful of breakaway warlords was Grand Moff Ardus Kaine. The successor of Grand Moff Tarkin created the powerful Pentastar Alignment that solidified Imperial power in the Outer Rim territories but removed a substantial portion of Coruscant's influence.
Supreme Leader Snoke, leader of the First Order in Star Wars, was modeled after Grand Moff Tarkin actor Peter Cushing, says designer Ivan Manzella.