Last mission is where you choose either Yuna, Rikku or Paine as your main person and that person goes up through a huge tower battling all the monsters in the game. Seems like a big waste of time. Last mission also has 1 more dressphere, which is a psychic thing or something. Only good thing about the game is Rikku

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I dont know if FFX-2+last mission has the original FFX-2 game in it (which was a boring game... no good storyline. FFX was really good and it shouldn't have gotten a shitty sequel)