ElectronicRocker on 16 April 2009
they first had to develop killzone liberation
when they released it on psp (2006)
then they started with the engine and killzone 2 development
and it was finished end of 2008 (got released later because of resistance 2)
btw
halo wars launched in march so it has its opening week in it sales while kz2 doesnt
sorry for my bad english, hope you understood everything
