"So be it. Let those who would resist discover what they resisted against." As he was claimed by the Force, anger - his only true companion - dissolved into nothing. This last curse was his parting gift to the galaxy, his now-dying apprentice, and his apprentice's son. As his existence faded, he sensed a gleeful laugh, one that would have frozen his blood just a few minutes earlier. Peering through the veil one last time, he saw his apprentice's son glance up, mistaking the deeper black for the darkness fading in front of him. "Your arrogance will be your downfall, like your father before you, young Skywalker." With that, the Emperor, the uncorrupted Darth, and the protector of the galaxy, was no more.
Anakin Skywalker, finally free from the shackles of his pain and anger, could sense the gaze of the oncoming storm. He wanted to warn Luke, to aid him in any way possible. He sensed his old masters and, perhaps with their powers, saw the despair that would tempt his son. But, Luke was stronger than he had been. "Like his mother, in that way," Anakin thought with a sad smile.
Luke wouldn't find solace in that despair and let it claim and consume him. Instead he would wall himself off and keep that poison from tainting the galaxy. "Damn hubris of the Jedi," thought Vader, "you aren't important enough to engulf the galaxy yourself."
"But, you may be a strong enough spark to keep the flame of hope alive." Anakin said. Luke stopped and looked at his father.
"What?" The failing equipment covering his father's body was a stark reminder of the punishment meant for him. Luke sensed the struggle for his father's soul still raging very close to the surface of Anakin. He propped his father up, unsure of how to help.
Vader angered at his helplessness. As he reached out to the Force for any answer, he sensed Anakin holding him back. "We could draw life from Luke. Not enough to kill the boy but enough to sustain us until…"
"No!" Thought Anakin. "Too many compromises led us to this. Too many deals. No more." He knew what he had to do. He had to remove the accoutrements of Vader, if he hoped to have the strength to give Luke a message.
While convincing Luke of the inevitably of his death, he struggled to hold back the man he had been for as long as Luke had been alive. He felt the strength in the eyes of his masters and knew they had given him the words Luke would need when the time came. This idea had driven Luke to the edge of his rage and it would pull him back from the brink during his time of need. As Luke pulled off his mask, he could feel Vader retreat from the unfiltered gaze of his son.
"Tell your sister, you were right."
Would that be enough? Would Leia's love of her brother be enough to save Luke, just as Luke's had been enough to save him? What was coming would tear the entire galaxy apart and Luke's self-imposed exile would only doom them further. "He saved me… and you can save him…" he didn't know Leia the way he knew Luke, so he didn't know if she sensed his last words.
Having won his final battle, Anakin Skywalker became more powerful than he could have possibly imagined.