When it comes to super villain smackdowns, few match the cold, calculated fury of Sith lord Darth Vader. In stark contrast, Superman represents the best of humanity bundled into tights and a Jerry curl. Smashed together, they'd put on quite the show -- a fight for the ages filled with world-shaking strikes and glowing red scars littered throughout the landscape.
On the surface, a bout between the two could be written off as an easy win for Superman. He is capable of punching foes into outer space and fast enough to circle a planet in the blink of an eye. However, his hypothetical foe Darth Vader doesn't possess any exploitable weaknesses to Kryptonite, nor any notable moral standards to be restrained by. Here's a breakdown at what could happen if Darth Vader and Superman went toe-to-toe.
Darth Vader
In the black corner: The Chosen One, Jedi council inductee and "Dark Lord" himself, Darth Vader. At 6'7" tall and a hulking 299 pounds in costume, Vader is truly a force to be reckoned with. He also boasts a multitude of incredible feats, such as tossing rebels aside with little effort using hands and yes, moving entire star ships using only his connection to the Force. However, Darth Vader possesses more abilities than just his physical strength and the Force to aid him in battle.
A cunning tactician, Vader was instrumental in wiping out the Jedi order on a galactic scale. He's also a master manipulator who isn’t above playing head games (particularly with his own son) to get what he wants. He is capable of reading and influencing lesser minds around him or simply using fear and intimidation in order to accomplish his needs; Mind control is an area where Superman has shown a history of weakness.
Vader is dressed in a cybernetic, lifesaving suit, bestowed upon him by Emperor Palpatine. The suit is lightsaber, projectile and temperature resistant thanks to the Mandalorian iron within it. His iconic helmet also comes with multiple vision settings (including ultraviolet and infrared) alongside strength enhancing cybernetics, capable of tossing hundreds of pounds.
Rarely ever caught with a blaster in hand, Darth Vader's preferred method of execution lies within slicing distance of his lightsaber -- which has a temperature of 45,032 degrees Fahrenheit (25 thousand degrees Celsius). For perspective, Earthly volcanoes on the hotter end can spew molten lava at 2,192 degrees Fahrenheit (1,200 degrees Celsius). All of these factors, coupled with the instantly recognizable crimson blade, form a Sith tank who enjoys the fighting up-close and personal.
Superman
In the red corner, standing at 6'3" tall weighing in at 235 pounds is a man who needs no introduction: The Man of Steel, Last Son of Krypton and savior of Earth: Superman.
Since previous iterations of this character contain ludicrous levels of power (such as the ability to sneeze galaxies out of existence), the frame of reference here will be the most divisive (and arguably weakest) modern iteration of Superman, from the New 52. Still, New 52 Superman has been shown as having strength enough to lift the weight of the Earth, with the stamina to do so for days on end -- making him a one of the strongest characters in the entirety of the DC Universe. With that in mind, magic and Kryptonite have always given Superman cause for concern, with the latter being what kills him at the end of his New 52 story.
When it comes to tools available to finish the job, this incarnation of Superman possesses super strength, speed, durability and a power unique unto himself: The ability to eject all the solar energy from his cells in order to produce a massive solar flare known as a "Super Flare".
Superman Vs. Darth Vader
As the two collide in a fictional death battle, one thing becomes abundantly clear: Darth Vader just can't cut it. While mind control should have been the deciding factor in this fight, instances of mind control on Superman require massive amounts of pre-meditation and forethought -- that, or Kryptonite (which hasn't been established in the Star Wars canon that we know of). In the interest of fairness, giving Vader time to prepare would also mean giving Superman time to prepare- This wouldn't be the first time the Man of Steel has learned psychic defenses given the opportunity.
Additionally, Vader lacks the ability to land a killing blow. Due to his Kryptonian physiology, Superman is powered by yellow stars like Earth’s sun and has been shown as flying through many like it, absorbing energy directly into his body.
Solar flares in nature can jump to over 40 million degrees Fahrenheit (20 million degrees Kelvin), dwarfing the temperature in a lightsaber exponentially. This is a show of force that originated within Superman's own body which he recovered from without issue, lending credence to the idea that a lightsaber, at a fraction of the heat, wouldn't do much damage -- if any at all. While Vader defenders may argue for the use of a red sun (which turns Kryptonians functionally human), there's a strong counter argument for then removing Vader's suit in the interest of fairness, an act which ends poorly for the Star Wars tyrant.
A fair fight only ends one way -- and that's a victory for Superman.