TLDR: Vader's realization that he tortured his own daughter on the Emperor's orders, coupled with his longstanding hatred of how Palpatine lied about his children, caused him to protect his other child from that monster even if it meant suicide.
Once he becomes Darth Vader, each evil act he commits shatters any hope or connection towards his previous life, which makes it harder for him to return to the light, but he ultimately escapes the dark side and redeems himself by sacrificing his life to save his son, Luke Skywalker, and kill the Emperor in Return of ...
Yes, he did turn back to the good side of the force at the end of Return of the Jedi. Now many will over complicate it by saying Anakin Skywalker returned or was resurrected within Vader and when that happened Darth Vader died and Anakin lived once more and so technically Vader didn't turn to the good side lol…
In his last final moments and with the courageous act of saving his son and turning on his former master, Vader turns back to the Light Side and dies as Anakin Skywalker. He then becomes a Force ghost, which you would then see at the end of the movie with his former friend Obi-Wan Kenobi.
There isn't any character in Star Wars more iconic or well-known than Darth Vader. Every Star Wars fan knows Anakin's tragic turn to the Dark Side in Revenge of the Sith, as well as his return to the Light Side in Return of the Jedi.
Given that he's never been drawn specifically to one side of the spectrum, it stands to reason that Luke truly is what's colloquially known as a gray Jedi; he uses both the light and dark sides of the Force while maintaining balance within himself. So he never turned to the dark side because he had no reason to.
Luke explains to his sister that part of his choice to become the Emperor's apprentice was due to his need to know why their father chose the dark side, learning that it was the result of fear and the tempting promise of power to combat it.
Although the decision to turn to the Dark Side was Anakin's alone, the choice did not come from thin air. His natural prone to impulsivity and emotion without the support systems he needed in place made it easier for Anakin to stumble down a path of darkness.
Shmi informs Qui-Gon that Anakin has no father, leading Qui-Gon to suggest that Anakin is a product of midi-chlorians (Force-imparting microorganisms). As the film progresses, Anakin leaves Tatooine to begin his Jedi training.
The short answer is yes, without a doubt, Vader regretted becoming a cybernetic monstrosity. First, there's the constant pain and discomfort from his suit. Worse, however, is the psychological pain. Vader destroyed everything he had ever known for a chance to save Padme.
Anakin does not have even the slightest bit of remorse. By the end, he feels nothing but anger. Although he feels regret for killing Padme, he still helps the evil Emperor. The film ends with Anakins standing side by side with the man on whose behalf he has committed all his crimes.
However, when it comes to who Darth Vader hates more than anyone in the Star Wars galaxy, himself and Obi-Wan Kenobi don't hold a candle to the true point of Darth Vader's hatred, Emperor Palpatine.
In essence, the more one holds hatred for someone, the more power that person has over them. By hating Palpatine more than anything, Darth Vader is admitting that Palpatine is the true source of his power, and is therefore far too important for Vader to kill (even on a subconscious level).
Why was Darth Vader so weak in Return of the Jedi?
Late Vaders total strength is a balance of variables. Age, his suit and his de-limbing lower his strength, but obviously his pain, anger and hate connect him to the dark side and make him more powerful.
Yes, he remembers everything about his past (just not based on reality), but he probably doesn't spend a lot of time thinking about it, and when he does, his memory of things is clouded and twisted by the lies of the sith, the dark side, and his own flawed thinking and character.
'Darth Wyrm' would fit with Sith tradition, and its original meaning - an archaic term for 'dragon' - would properly convey Luke's incredible power, and even has some poetic meaning as the inversion of the Jedi 'knight' he could otherwise have been.
The realistic answer seems to be, yes, Anakin in his prime could have defeated Luke Skywalker (in the current canon) if they battled one-on-one. The main reason behind this is Luke's lack of formal Jedi training, at least when it comes to combat.
While he had suffered fatal injuries from the Emperor's lightning, Vader's redeeming final act restored his consciousness to Anakin Skywalker, and he had one last moment with Luke before peacefully accepting his death.
Rey is Anakin's half sister, and Palpatines relations to Rey through the force. Rey is a genetic experiment/force experiment of immaculate conception orchestrated by palpatine. So Rey is Palpatines daughter or grand daughter, in a metaphorical sense. The same way Anakin is Palpatines son through the force.
The only explanation given in Revenge of the Sith for Padmé's death is that because there is nothing wrong with her physically, she has lost the will to live after seeing Anakin turn to the Dark Side. This however does not hold much weight.
Vader's redemption in Return of the Jedi was not just about saving his son; it was also a defiance of the dark side's corruption and his own past as a Sith Lord. Vader's decision to block Luke from killing Palpatine was motivated by his knowledge that it would corrupt Luke and lead him down a similar path of suffering.
The wampa attack stemmed from a real-life car accident star Mark Hamill suffered in January 1977. In J.W. Rinzler's book The Making of Star Wars: The Empire Strikes Back, Rinzler describes Lucas' suggestion that they explain Hamill's injuries as "'Luke crash in beginning (scar on face).
Luke confronted the Dark Spirit in the form of Darth Vader within and defeated it in a lightsaber duel, dipping into the passion of the dark side in the process. It was there that he realized what would happen if he turned to the dark side of the Force. Behind the mask of Darth Vader, he saw his own face.
Although Anakin and Luke were both tempted by the dark side, the latter never actually switched sides and became a Sith Lord. Anakin, on the other hand, chose to strike down Mace Windu instead of Palpatine, pledged himself to the Sith, and took on the moniker of Darth Vader. Luke always stayed on the light side.
