"Skywalker," Kylo Ren's coral eyes glowered at his old Master. "You just won't stay dead, will you?" His voice challenged, but his tone was flat.

He stood, mid swing, his lightsabre searing red against the blackness of the cavern walls. His chest heaved with his exertions. The black quartz, as ever, showed nor chip, or mark.

Luke looked hard at his former student, and then down at himself. He found himself sitting, cross-legged, on a small ledge that passed along the wall of the cavern. A faint green glow surrounded his legs. After a moment, he looked up again, and motioned towards the wall. "You do know that's rock, don't you? Or has the Dark made you stupid, as well as rotten?"

Rotten is the word, thought Luke. Ren stood before him, soaked to the skin, and with barely a tunic left on his body. His torso looked, as ever, as if hewn from marble beneath the black fabric. But his skin was so pale as to be translucent, and marked with bruises. Blood streaked across his flank, hands and face. His once lustrous hair was overlong and tangled, framing a wintry face set with red, glaring eyes. Black veins snaked across his temples, and down his neck.

He's literally poisoning himself. Luke's thoughts turned momentarily to his father, and that moment he first pulled that black mask from his face. Luke.

Kylo shrugged. "I came for answers. But it shows me nothing." But he lowered his lightsabre anyway, almost welcoming a distraction. He withdrew it with a buzz, hitched it to his belt then returned his eyes to Luke's. "Nothing of value, anyway."

Then Kylo started to pace, up and down, looking sporadically as the wall, and then his feet.

Luke watched his former student closely. After a while, he asked, "So. What did you see?"

"Why should you care?" spat Kylo.

Luke studied Kylo's face as he replied, "Well. It appears neither of us have much to lose. Or do, right now. So... "

Kylo halted, and rocked back and forth on the balls of his feet. The raw energy pulsing from his was palpable.

"Vader," he said, after a while. Then, turning his face to the wall, "He just couldn't kill him."

Luke's eyes narrowed. "Who?"

"Anakin." replied the younger man, curling his lip as if chewing on bitter lemons. "At the crucial moment, he failed. Because of sentiment."

Luke watched as Kylo started again to stalk the cavern, his thoughts continuing their agitation. For a second, Luke saw a flash of a boy he used to know in those dark, brooding eyes.

"So - Vader, your idol - disappoints you?"

The younger man stopped again, and clenched his jaw as he considered the question. "No," he said, presently. "But...he was trapped." Then, seemingly to himself, Kylo continued, "And where he failed, I could still succeed."

Luke, despite himself, felt his blood begin to warm. "Trapped? Then it was a trap of his own choosing!"

As soon as he had said it, Luke instinctively knew he had made a mistake. A voice in his head agreed. Speak, you must not. Instead, listen.

Yoda?

As soon as he finished speaking, Kylo spun and stamped his right foot, lowering himself to face Luke as he unsheathed his sabre again. His fighting stance had always been thus, Luke thought; challenging, loose, and primal. I shouldn't be baiting him.

"The expectation on his shoulders!" hissed Kylo. "The weight of being the chosen one. But could he choose?" His eyes were glowing near -scarlet against the pulse of his sabre. Then he let out a roar. "I left you before you could indoctrinate me into the Skywalker lies! The Jedi - dedicated to knowledge. But not about human needs! Dedicated to the truth. Except when it comes to speaking the sordid truth of Lord Vader!"

Luke winced at the reference. So this was part of the rub.

Where with this are you going, came the voice.

"I'm not sure," murmured Luke.

Careful, you must be.

Luke had been party to Leia's insistence that Kylo Ren never knew that his grandfather had been the Dark Lord Vader. At the time it had seemed the right choice, to protect him. But later, the truth came out at the New Republic Senate, ruining Leia's career.

The painfully public fallout landed yet another blow into Ben's already shaky view of his family, who he had clearly regarded as unreachable, almost neglectful, especially his wandering father. The young man was already bewildered, unsure of his place despite his obvious talents. In retrospect, Luke had underestimated these combined effects on his psyche. Snoke had not.

Luke felt another sensation rise in his chest. Shame. He looked steadily at his nephew.

"We did love you," he said, simply.

"Then why did you abandon me?" yelled the younger man, lifting his sword. He sliced into the air, crashing his blade into a nearby stalactite. The rock crashed to the ground. "Because my path was already chosen, wasn't it? And who needs direction when his destination is already so well mapped...!"

His chest heaved again with the exertion of the swing. For a moment, it looked as if he would faint. But after a slight stagger, he regained his footing, and once again swung around to face his former Master.

"You felt trapped," said Luke. It wasn't a question. The younger man just stared at him. "And alone."

Luke raised his hand and stroked his long, grey beard. He noticed the blood pouring out of the wound on Ben's back.

"So are you now free?" asked Luke.

Again, he noticed Ben sway slightly to one side as he spoke. The young man, perhaps starting to feel his own wounds, once again allowed his sabre to withdraw. He scanned around for somewhere to sit. His eyes looked around, but didn't seem to see.

"I thought it would be easier..." he murmured, his words now starting to slur. "To destroy my past. I had less brainwashing... than Vader. And I chose this. I actively chose this path! To escape your poison..."

He staggered forwards again. but his eyes flared. His rage was a wildfire... ebbing, raging, calming... then destroying...

"But every time I make the right choice, it wrong," he suddenly blurted out. His low voice trembled. "It gets harder."

And then, "I can't step forward, and I can't step back..."

"Its not too late," said Luke, and he meant every word.

"You lie!" once again, that anger in Kylo's voice. "You know what I've done."

Luke gestured at the wall. "But Vader... my father.. he came back..."

"Are you a fool?" cried Ben, half sobbing now, but a growl still edged his voice. "Your father chose to die. For you. He knew by facing Palpatine he would die. Death is easy! A welcome release!" The young man was now openly sobbing. "But I don't want to die. I want to live. But how can I live?"

Kylo gestured at the black mirror in front of him. "I'm...I'm..."

Luke lowered his legs and slowly raised himself up. He took a slow step from the ledge, moving quietly, slowly, like a rider breaking a mustang. He drew closer to the younger man, and whispered, "But there are still people who believe."

Ben let out a strangled laugh. "Who. You?" His legs then went out from under him, and he dropped to the floor.

Luke felt the urge to rush towards him, but held himself back. He said nothing.

"She does." said Ben, quietly. And Luke realised then, that the connection had been real. I thought he was toying with her. Using her. But in fact...

"Or, she did," Kylo then spat. "And I hoped... we could create something new. Because after everything I've done... she almost gave me..."

"Hope?" Luke's voice echoed across the cavern walls.

Kylo turned his big, dark eyes to Luke's. "The only thing I know," he said, slowly. "Is that she has to live. But I can't lead the First Order and not kill her. And it would deny everything I believe to become Jedi. So I can't..."

For a moment, both fell silent, listening only to the drip-drip of water, falling into the cavern from above.

"So what do you want, Ben?"

"To be myself!"

"And who is that?"

Suddenly Kylo lurched to his feet again, and threw out his sabre. "A fool, who killed everything, to be left with nothing!" he cried. His lightsabre roared to life, as he began, again, to smash at the rocks surrounding him. "But you... don't... care! You're just here to mock me! You're just here to... watch me die..."

Luke pulled himself to his full height as he watched his nephew lash out at his surroundings. Without thinking, he cried, "Then make it worth something! Create something!" Luke stepped forwards. "You're right! We go so much wrong. I got so much wrong. But learn from me. Learn from our failures. My failure. Please."

"How...can...I build... from.. these ashes...?" cried Ben, his aim now spinning out of his control as his legs started to buckle again from under his feet.

"Reach out to her!" Luke cried. "She doesn't belong to the Light. She's just ...herself."

Ben stopped, his chest heaving. He looked up, his eyes filled with tears, and swung his sword down to his side. Suddenly, he walked towards the wall again, and placed a hand on its mirror like surface.

He looked within, and as he did so, his face crumpled.

Han, thought Luke. He sees Han.

Ben let out a terrible, pained cry, and lifted his lightsabre again. Once more, he wheeled around, crashing his sword into the rocks around him. Sparks flew, as more tiny shards of rock and glass sliced into his face and body. Luke's face softened, and he felt nothing but pain and compassion for this poor, lost, young man.

Rage this is not, said Yoda. It is sorrow.

Finally, Ben gasped, staggered, and fell to the floor. This time however, he passed out, and lay quite still. His lightsabre skittered across the floor towards Luke's feet.

"Sleep, my prince," said Luke, slowly disappearing, as he heard the cries of the Knights of Ren nearing the cavern, looking for their master...