Okay, I've loved the whole saga my entire life, and a question popped into my head...hopefully there can be some good discussions out of it.
We all know the whole "Rule Of Two" among the Sith -- one is the master, one is the apprentice. There also seems to be the Betrayal of Opportunity among the Sith as well....where one kills the other, whether it be out of necessity or power grab or whatever....
Which leads me to this question -- at the of Revenge Of The Sith, why didn't Palpatine kill Vader? Why the need to keep Vader alive? He went through all of the trouble of "reassembling" him into the mechanical Vader that we all know and love. Vader obviously can't summon Sith Lightning due to robotic limbs. By all accounts, Vader was a scarred and broken man. Why the need? (Other than, obviously -- "because it wouldn't be a PREQUEL!")
After playing Dark Side since the game release, I've seen a pattern of Dark Side behavior, and that question came up in my mind. I was just curious, it seems like a contradiction in Sith behavior to me.