Zax on 09 February 2014
According to this site (take it with a grain of salt) Final Fantasy XIII sold almost 7.2 million copies. Final Fantasy XIII-2 sold 3.2 million copies.
Personally I liked both games and think it's a shame XIII-2 didn't sell more but oh well.
Can Lightning Returns sell 2.5 million copies? (another 2.1 million copies)
