The season 5 two-hour finale only reaffirmed my theory that the show is based on a game, and not backgammon. Like the centuries old game of chess, there is a black king and a white one. Then 15 more pieces that fight along side their king and queen. Perhaps Jacob is the white king and brother/ enemy is the black king. I think Jacob chose his pieces, the Losties, carefully to try and defeat the black king. I also doubt Jacob is dead, and I believe that, although Locke is being used by the black king, he is not dead and still a white Knight for Jacob's side. His reference to Locke/ black king possesed white knight that I think he is, that " They are coming" is the Losties stuck in the 70's were coming back to the present to defeat the black king.