God of War: Chains of Olympus uses a proprietary, in-house engine referred to as the Ready at Dawn engine, which expanded on the engine created for their previous game, Daxter, to include a fluid and cloth simulator. The camera system was modified to cater to the fixed cinematic camera for God of War gameplay, and the lighting system was reworked to aid in presenting realistic graphics. The game was originally designed for the PlayStation Portable's restricted 222 megahertz (MHz) processor. Ready at Dawn repeatedly contacted Sony regarding increasing the clock speed of the PSP on account of the difference to the game and had developed a version of the game with higher speed. Sony released a firmware upgrade that allowed games to use the full 333 MHz processor. The faster processor allowed for more realistic blood effects, lighting effects, and shadows as well as improved enemy intelligence. The upgrade, however, noticeably decreases battery life. After the game's completion, Game Director Ru Weerasuriya stated multiplayer options and other puzzles, characters, and dialogue had to be removed due to time constraints.
