Note that I do not own the Star Wars franchise. As much as that would be a dream come true, it obviously wouldn't happen.
The story of this fanfic is about Luke and Vader (and others) in an uncanon alternate universe.
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A long time ago in a galaxy far, far away...

Former Jedi, Anakin Skywalker, fought with his own master in a firey planet named Mustafar. His master, Obi-Wan Kenobi, won during their battle on Mustafar. Emperor Palpatine called help to revive the nearly dead Anakin, who was left to burn beside flowing lava.

Palpatine created a suit for Anakin. It was built for Anakin to survive even when burnt. Anakin's life depends on his suit, who keeps him alive as well as his helmet.

-Present Time-

"No, I am your father!" Vader said, clenching his fist.

"No... No! That's impossible!" Luke screamed, grabbing onto.. Whatever he is currently grabbing to avoid falling.

"Search your feelings, you know it to be true!"

"Come. Together, we can rule the galaxy as father and son!"

"No... I'll never join you!" Luke let go of what he was holding onto without hesitation. He fell, but luckily, he entered some sort of suction tube, but it brought him under Cloud City. Luke managed to grab onto pole or some sort.

-Vader-

Vader knew Luke didn't die. He felt it. But he returned to the Death Star II, which is still under construction.

-Leia-

"Wait!" Leia said.

"I know where Luke is..."

"Okay, where is he?" Han replied.

-Luke-

As Luke saw the Millennium Falcon coming towards him, he knew he'll be saved.

"Come on, drop down!" The man said.

Luke dropped down and entered the Millennium Falcon through it's hatch on the roof.

"And you are...?" Luke said to the dark skinned male.

"Lando. Lando Calrissian" Lando replied.

-Vader-

"Son.. Come to me." Vader called Luke through the force.

Knowing that Luke has ignored him, and his offer to join the dark side, Vader would have to try harder in order to convince him to join the Sith.

"Some day, he will join us. Master" Vader said to Emperor Palpatine.