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.
To show that he had some remorse. Part of him knew what he did was wrong but he thought it was the only way to save Padme.
Anakin admits to Obi-Wan that he has been arrogant and unappreciative of his training, and apologizes to his master. Obi-Wan assures Anakin that he is proud of him, telling him that he has become a "far greater Jedi than I could ever hope to be."
For years, Vader hated Obi-Wan, having been struck down by his mentor and left for dead while also believing the Jedi had worked to turn his true love Padmé against him. However, there's another, far darker reason Vader hated Obi-Wan so obsessively.
He does. Right at the end. With Luke crying over him and Vader sensing his anguish and pain he had inflicted on all those who had cared for him.
In the material around the film from the Legends timeline, it's established that by the end of Star Wars: Episode III - Revenge of the Sith, Kenobi was one of the characters who knew Anakin's Sith name was Darth Vader. However, what he didn't know was that he was still alive after Mustafar.
Arguably, most Star Wars plot points revolve around characters simply not knowing something, very often about their family history. But, on top of all of that, the biggest reason Obi-Wan doesn't know Anakin is alive is that the last time he saw Anakin Skywalker in Revenge of the Sith, Ben literally left him for dead.
Vader responded “I am not your failure, Obi-Wan. You didn't kill Anakin Skywalker. I did.” This allows Obi-Wan to finally accept that Anakin is truly gone and that there was nothing he could have realistically done to save him.
He slays Sidious and returns to Obi-Wan, begging for atonement by execution, only to be met with true forgiveness instead. But just as this fantasy Obi-Wan refuses to strike his former friend down, Vader refuses to turn his back on the dark.
Before he discovered Vader had survived Mustafar, Obi-wan lived with the regret of killing his son, brother and best friend. After, he regretted not killing him and wondered if he had only made things worse by pushing Anakin further into dark side and Palpatine's arms.
Obi-Wan knew it was only a matter of time. So, he made the difficult decision to use his learnings and become one with the force, rather than let Vader decapitate him.
Vader had a great amount of respect for Obi-Wan as a Jedi and their former teacher-pupil relationship. He even referred to Obi-Wan as his “old master” when they fought in their final confrontation.
No. Her dying words were there is still good in him. Obi-Wan didn't tell her what happened after she lost consciousness on Mustafar.
He regretted it the moment he did it. He asked himself what he just did, dropped his lightsaber, and was visibly ashamed of himself when Palpatine anointed him a Sith Lord and began his speech about wiping out the Jedi.
First and foremost, Obi-Wan didn't want to have to confront and try to kill Anakin, we see this all the way until their final conflict in their duel where Obi-Wan pleads with Anakin to not make him do what he knows he'll have to do if Anakin tries to attack from the low-ground.
Master Yoda knew that Darth Vader was once Anakin Skywalker- the boy he sensed too much fear in to train way back in Star Wars: The Phantom Menace.
If you are asking about Vader post-Mustafar, then no, she doesn't. Padmé doesn't seem to know Obi-wan cut off his limbs and left him to burn alive, Obi-wan didn't believe Anakin to be alive and Anakin's surgeries were still happening as Padmé died so there was no way for her to know.
Anakin Skywalker had a vision of himself becoming Darth Vader. As the Chosen One, Anakin Skywalker had extremely powerful Force visions in his dreams when asleep, and his visions were never known to be wrong.
Can't Stand - Emperor Palpatine. Some would say that Palpatine represented Vader's only friend and companion, but real fans know that this is anything but the case. In many ways, Palpatine enslaved Vader and, over the years, Vader undoubtedly grew to resent his master.
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.
On Obi-Wan Kenobi, Darth Vader had been operating for ten years, making him 32 years old when he encountered his old Master, who had been hiding since Order 66. The pair fought twice, but it was during their second clash that Vader uttered a harsh truth.