In the end, Thanos' neck is only as strong as his skin. Even if his lightsaber can't cut through Thanos' invulnerable skin, Darth Vader can still Force choke the Mad Titan and prevail.
Thanos wields more power and authority than Darth Vader, existing as a stronger and more capable villain overall.
Thanos is one of the most powerful and dangerous villains in the Marvel Universe and his plethora of powers, titanic strength, and fiendish intelligence would allow him to defeat Vader. Vader's lightsaber may be able to pierce Thanos but it would take time, and Thanos would just blast the armored Sith away from him.
Vader would immediately crush Thanos when the fight began. No matter how talented Thanos is, he does not possess the Force, while Vader possesses. Thanos can use his Gauntlet, but without the Force, there is no guarantee he can keep it long. The Force is powerful enough to move the object away from one to another.
In Star Wars Legends and Canon, Galen Marek (Starkiller) is the only Jedi (other than Obi-Wan Kenobi) to put a beat down on Darth Vader/Anakin Skywalker.
We would have to give the victory to Darth Vader. While the two dark lords seem perfectly matched on their villainy and power, Darth Vader's lightsaber and ability to immediately use the force to choke Voldemort, without chanting any spell would end this showdown in seconds.
As Darth Vader, Skywalker was believed to have had roughly eight-tenths of the strength of the Emperor. Nevertheless, Vader wielded tremendous power and skill, enough to use the Force to overpower almost any opponent he could not defeat with his lightsaber.
Highly unlikely. Even if Vader is the most powerful user of telekinesis, which he's not, he would not be able to lift up Thor's hammer. The enchantment on Mjolnir will still apply to force powers.
This is an easy one. There's not a person in the Star Wars lore that can beat the Hulk. You could throw every Sith Lord and beings with the force his way and they'd all lose. One by one or all at once, the Hulk would beat them all.
In Avengers: Infinity War, Thanos obtains the six Infinity Stones and places them within a gauntlet built by Eitri, so that he can snap his fingers and eliminate half of all life in the universe, which he believes will bring a balance that will prevent greater catastrophes from fighting over resources.
The blade has even been used as a tool to weld metal. Other times, the lightsaber has been shown to cause bleeding wounds in the flesh, sometimes accompanied by burns.
Phrik. This rare metallic compound was resistant to lightsaber strikes and was used in the construction of battle armor and weaponry due to its light weight. Phrik was first developed by the Arkanian's, a near-human species which resided on the frozen planet of Arkania.
Luke Skywalker
However, once Luke fully embraced his power in Star Wars: Return of the Jedi, he proved that he was indeed stronger than Darth Vader and struck his father down.
Although Thanos has a higher intellect than Vader, the Dark Lord of the Sith is wiser regarding battle strategies and war experience. Despite this, Thanos' raw power should not be underestimated, even against the strongest of the Empire's tactics.
Adam Warlock is a being of immense power. He has superhuman strength and agility, can manipulate energy beyond comprehension, and has a healing ability that would mean much of Vader's physical attacks would be unsuccessful. This fight would be over pretty quickly, and Warlock would be the victor, no question.
Forged by dwarves in the heart of a dying star, the weapon is enchanted so that it can only be lifted and wielded by those who are worthy of its powers. Both in the comics and the MCU films, many characters other than Thor himself, both heroes and villains, have been able to lift Mjolnir.
Why is this such a big deal? Well, for starters, the hammer in question, Mjolnir, can only be wielded by those who are considered “worthy,” a little mystical insurance policy put on it by Thor's dad, Odin. It's pretty cool to see the Avenger who is the purest of heart officially deemed “worthy” of the weapon of a god.
This is reflected in the inscription on the side of Mjolnir, which states: Whosoever holds this hammer, if he be worthy, shall possess the power of Thor. For almost the entirety of Marvel continuity, this has exclusively been Thor.
It appeared that Darth Vader was more machine than we thought. 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.
Vader used his pain and anger to fuel his Dark Side powers, becoming one of the most powerful Sith ever and perhaps the most feared. He was the enforcer of the Empire, using his red lightsaber and black armor to strike fear into his enemies, becoming an instrument of terror to fight the Rebels.
Anakin Skywalker was the Chosen One, conceived by the Force itself. According to Star Wars: Episode I - The Phantom Menace, he had a midichlorian count higher than even Master Yoda. This meant he had the potential to access the Force and achieve feats no other Jedi or Sith had ever managed.
Aside from agility and telekinesis, Yoda could absorb and redirect Force attacks, like lightning. Because of his higher understanding, he would easily overcome Darth Vader in a fight, though that doesn't mean it wouldn't be a difficult battle.
In the process, the Emperor enhanced his apprentice's abilities as he earned back his spot in the Empire. Growing in his power, Vader's confidence that he can kill his master gives him a new perspective. “You can destroy the Emperor.