1 - Original War
Platform:
PC (Microsoft Windows)
Released on Jun 15th 2001
2 - UFO: Aftermath
Platform:
PC (Microsoft Windows)
Released on Oct 03rd 2003
3 - UFO: Afterlight
Platform:
PC (Microsoft Windows)
Released on Dec 01st 2006
5 - UFO: Aftershock
Platform:
PC (Microsoft Windows)
Released on Oct 21st 2005