Darth Vader simply looked at the destruction of the Rebellion fleet with disinterest, his focus more directed towards his son. Luke, his name was, and Vader could see so much of himself-no, of dead Anakin Skywalker- in the boy. His impatience, his piloting technique, his knack for getting himself into danger, and, surprisingly, his goodness that Vader, no Anakin, was capable of. Shielding himself from Emperor Palpatine to hide his emotional conflict, Vader even grinned as Luke refused to join the Dark Side but quickly scowled as the emotional war raged within him. Vader was facing a most interesting conundrum. Did he truly wish for his son to go down the path he did (and regretted so many times)?
The answer was quite simple: yes, he did. Luke's turn would allow Vader to finally overthrow the Emperor, allowing the dynamic duo to rule the galaxy as father and son the way Vader wished for it to be run. Slavery would finally be outlawed, Vader personally see to that and he would finally earn the respect he so desperately needed. The galaxy would also finally be allowed to let Force-Sensitives live, and his Sith army would come to fruition. Luke would finally know real power and the meddlesome rebellion would be truly crushed. It would not be the peace he envisioned so many years ago during the Clone Wars, not by far, but the Force would never be at conflict again. There would be a simple, yet powerful, darkness that would pervade the galaxy, and his name would be remembered (and feared) for generations upon generations.
The answer was quite simple: no. Vader-no, Anakin- could often feel the call to the Light Side and often mourned the Jedi's demise. Yes, they were corrupt and arrogant, with Obi-Wan being the most insufferable of them. However, their mission was true and pure, and Luke's fall, for it would be a fall, would ensure they would be extinct. Vader made sure of that. Vader (no, Anakin, ANAKIN) regretted his path many a night and he didn't want Luke to suffer the same mental fate as him; the nightmares were constant and the anger was his companion. Luke represented all that was pure and good in the Force and the galaxy, and the Sith Empire would never fall if he came to the darkness that so called to him in his very non-Jedilike anger. However, Obi-Wan's training kept Luke true, even Vader was impressed. So, when Luke called his lightsaber to his hand (his accuracy with the Force was most impressive), Anakin and Vader were surprised.
Being the dutiful slave he was (not for much longer, he assured himself), he blocked Luke's lightsaber with his own, and the fight began in earnest. With a start, Vader senses Luke's anger and realizes that perhaps, just maybe, the Dark Side has won yet again. The fight is short, but violent, and Vader realizes that Luke Skywalker is a fully fledged Jedi Knight now, or is as skilled with a lightsaber as one. Vader quickly becomes defensive, blocking strike after aggressive strike. With a start, Anakin, not Vader, realizes that his own son is trying to kill him. Before even a full minute has passed, Darth Vader, off balance, flips, or rather, falls down the stairs, landing rather ungracefully. Vader looks up at his son, both pride and anguish on his face, even if Luke (and Palpatine) cannot see it.
Vader, or rather, Anakin, looks up at his son, proud of his skill as a Jedi (or Sith, if the Dark Emperor has his way) and dedication to the Rebellion (brave scum they are). His anguish also exists in Luke's fall to the darkness and possible willingness to kill his own father. Before Luke can do anything, however, the Emperor laughs. "Good. Use your aggressive feelings, boy! Let the hate flow through you!"
Luke glances at the Sith Master behind him, the true object of his rage. Ashamed, Luke glances away as he realizes he was channeling the Dark Side of the Force and he lowers his weapon, steps back, and allows Obi-Wan's training to come back to him, driving the hate from his being. Angered, Vader allows the anger to flow within him and through him, feeding the Dark Side like he was taught. The Sith practically spits his next comment, "Obi-Wan has taught you well."
"I will not fight you, father."
Lord Vader watches his son meet his destiny at the hands of the one he calls Master. Within him, conflict is clear. Anakin Skywalker remembers Padme, his beautiful angel, and his love for Obi-Wan Kenobi and Ahsoka Tano. Vader remembers his commitment to the Sith Order and his galaxy, his Empire. Finally, when Luke begs him, Anakin the one he called Jedi, his father for help, there is no other option. Anakin does what he should have done over twenty years ago, before Order 66. Anakin betrays the Sith and fulfills his destiny. "NOOOOOOO!"
Vader hardly registers the pain of the Force Lightning coursing through his body, destroying his life support suit, and killing him. In a swift, bold move (for that is what Skywalker's are good at doing), Anakin picks up the Emperor and throws him down the shaft, destroying the last of the Sith and bringing balance to the Force. Collapsing by the railing, Anakin takes deep (yet shallow) breaths, trying to hold on to tell his son that one thing he never got to and always wished to. Begging to the Force, he pleads to live just a while longer, just until he can say that Luke was right, and that he loves him. However, for the first time in his life, the Force disobeys its son, throwing Anakin into darkness. Before the dreaded darkness returns, however Anakin begs one last thing from the Force. "Make things right. Make it Light." And then, he knows no more. Darth Vader dies Anakin Skywalker, a Jedi Master.
Luke opens his eyes, registering the shock of the lack of pain in his body, and more importantly, the shock of the appearance of the still form next to him. Barely taking a moment to observe the fact that he is no longer on the Death Star, he rushes to the form, attempting to help. The young man with curly brown-blonde hair groans and opens his eyes' their appearance similar to Luke's own. The figure, obviously shocked, gasps, "Luke!"
Two Jedi look upon the scene with interest. "Master Qui-Gon, wha- how?"
The older of the two looks at his padawan with an equally confused expression, "I don't know, Obi-Wan, but I sense we will soon find out."