The first game has currently sold 6.3 million (Vgchartz need to adjust the PS3 numbers in Japan). It'll probably chug along to 7 million eventually.
Final Fantasy X-2 sold 5.2 million can XIII-2 surpass those sales?
Its obviously not gonna sell as well as the original game and 5 million may be pushing it, the reception on the game was pretty mixed so alot of XIII owners probably wont buy it. However XIII-2 could possibly be better than the original if they fix how linear it is, Square already knows people had a problem with that so it could be more open world like and thus get a better reception.
So itd need to sell around 1.5 million on the Xbox 360 and 3.8 million on PS3 lifetime to sell 5.3 million surpassing X-2.








