text: 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 (2006), 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 decreased 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.
  Audio
  Two of the voice actors returned from the previous installments to reprise their roles, which were Terrence C. Carson and Linda Hunt, who voiced Kratos and the narrator respectively. Erin Torpey adopted the dual roles of Athena and Eos. Fred Tatasciore, who voiced different characters in previous installments, returned, and in this game, voiced both Atlas and the Persian King. Carole Ruggier and Michael Clarke Duncan did not return to reprise their roles, which were Athena and Atlas respectively. Voice actor Dwight Schultz voiced both Charon and Helios; Debi Derryberry voiced Calliope and continued this role in a later installment; and Marina Gordon provided the voice of Persephone. Brian Kimmet, Don Luce, and Andrew Wheeler provided the voices of several minor characters and Keythe Farley was the Voice Director.