I’m wondering if Snoke tells Kylo that in order to become a Sith, he must face off with not only Rey, but Luke as well, in order to become a true Sith. If he kills them, he WILL be as powerful as Vader.

I think in a way, it will be a mirror of TESB, where Luke rushes to fight Vader, so will Kylo Ren, but in doing so, it will be his down fall. He will get injured and actually have to where a breathing mask, just like Vader did, modified of course. However, we probably won’t see that mask until Episode IX.

Luke wanted so much to be Jedi and he fulfilled that destiny. Kylo is the exact opposite, he wants to be a Sith and will do ANYTHING to fulfill his destiny.

As for Rey, that’s a completely different story, one that will make more sense after Episode VIII.