The Killzone series first game was Killzone released on 2nd November 2004.
2004
Killzone
2nd November 2004
2006
Killzone: Liberation
31st October 2006
2009
Killzone 2
25th February 2009
2011
Killzone 3
22nd February 2011
2012
Killzone HD
23rd October 2012
2013
Killzone: Mercenary
4th September 2013
Killzone Shadow Fall
15th November 2013
Killzone: Shadow Fall