Even if you manage to download an archive, there is no guarantee it will work. Emulation requires specific file structures. If the ISO is ripped incorrectly or if the archive is corrupt, the emulator will crash immediately upon loading.

There is no official God of War 3 because the game was never natively released for Android or mobile platforms

If you have a high-end device, you don't use OBB files; you use or cloud gaming . 1. PS3 Emulation (Extreme Hardware Required)

. "OBB" files are specific to native Android applications, while God of War 3 was originally developed for the PlayStation 3.