Two years after the Helghast assault on Vekta, the ISA is bringing the fight to the enemy's home world of Helghan. Taking the role of Sev, the battle-hardened veteran of the special forces unit known as the Legion, players will embark upon a mission to the planet Helghan to capture the Helghast leader, Emperor Visari, and bring the enemy's war machine to a halt. For Sev and his squad, the invasion of Helghan is just the beginning. Tasked with securing Pyrrhus, the Capital City, the team quickly discovers that the Helghast are a formidable enemy on their home planet. Not only have they adjusted to the planet's hostile conditions, they have also harnessed a source of power from the environment that can be used against the ISA. Sev and his team soon discover the fight is greater than simply addressing the enemy forces; the Legion must also learn how to handle the effects of the fierce enemy planet.

With an extensive, story-driven single-player mode and thrilling multiplayer mode, Killzone 2 offers a host of new elements that caters to both hardcore and casual gamers alike. The game features highly atmospheric environments that respond accurately to weapon fire as players storm through the world of Helghan. The harsh climate and conditions of Helghan are also a factor, forcing players to adapt new tactics to survive. Proprietary tools and technology such as deferred rendering techniques are implemented to create advanced effects, such as ultra-vivid and detailed character animations and environments. Advanced cinematic effects are used to provide unprecedented visuals, including motion blur, internal lens reflections, and depth-based color grading that will let players experience gameplay that is sharp, detailed, and vibrant. Additionally, Killzone 2 supports 7.1 surround with location-specific audio, providing players the opportunity to experience sound and music that are not only dynamic but in context to indoor and outdoor locations.