 God of War III was first mentioned by Cory Barlog at a God of War II launch event, and it was officially announced at the 2008 Electronic Entertainment Expo (E3). After the first eight months of development, Barlog left Santa Monica for unexplained reasons and Stig Asmussen (lead environment artist and art director on God of War and God of War II, respectively) became director. Asmussen said that one of the greatest challenges in developing God of War III for the PlayStation 3 was the "complexity of everything"; individual tasks, such as designing Helios'decapitation, could take a year because the "level of detail [that was] expected [was] so high and intricate, it [crossed] multiple departments." He said that the PlayStation 3's hardware capabilities allowed more flexibility in character creation and interaction with the environment. The engine for God of War III was ported from the first two installments to the PlayStation 3. As the game was being developed, the code department swapped out PlayStation 2 components with PlayStation 3 components. They replaced the renderer, the particle system, and the collision system. Although they were re-using the engine from God of War II, the core engine for God of War III was brand new. Between E3 2009 and the time the game shipped, morphological anti-aliasing (MLAA) was added, which graphics engineer Ben Diamand said "improved edges dramatically and saved substantial amounts of frame-rate." Diamand also said that "depth-of-field, motion blur, crepuscular 'god' rays and refraction were either added or improved in quality and speed" during that same time period.
