Finn: You were a spicerunner?
Poe Dameron: And you were a stormtrooper?
Rey: You were a spicerunner?
Poe Dameron: And you were a scavenger? C'mon, guys, we could do this all day.
Luke Skywalker: No one's ever really gone.
Luke Skywalker: The force will be with you.
Leia Organa: Always.
Poe: Somehow, Palpatine has returned.
Poe Dameron: What are you doing there, Threepio?
C-3PO: Taking one last look, sir. At my friends.
Palpatine: Your journey nears its end.
Rey: People keep telling me they know me. No one does.
Kylo Ren: But I do.
Luke Skywalker: We've passed on all we know. A thousand generations live in you now. But this is your fight.
Answer: Palpatine has been manipulating Rey and Kylo Ren from the very start, bringing the pair together and instigating fights between them. He is trying to make Rey stronger so that when he takes over her body, she will be powerful. Palpatine can partially see the future and knows that Kylo will not be successful in actually killing Rey, but that their constant fights will cause the two to grow more powerful. Because he can see part of the future, he knows that eventually Rey will triumph over Kylo and "kill" him, and then come to confront him directly. He doesn't count on Ben Solo coming back to face him which winds up being his undoing.
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