I think the most important part about the Star Wars comparison that is being missed is that they weren't all sequels. Think about all the back information we can learn about the Rapture crew!!!
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Isn't everyone interested in seeing how Andrew Ryan used to be a little slave boy who raced his way into freedom?
What about his abnormally large ADAM count, leading to his genius and the creation of Rapture?
Or, the greatest moment of Ryan's life, meeting Jack's (your character's name, if I recall correctly) stripper of a mom as a young girl, when she used to frolic around, flashing her parts to the playground boys for a nickle.
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There are so many great moments that we're going to miss out on by these games not being made...Who's with me for an online petition?