For reverse engineering, modding, or audio extraction, the .fat is the key to understanding the contents of the .dat . No public documentation exists from Ubisoft, but the community tools have fully reverse-engineered the structure. The format is stable across Dunia Engine games ( Far Cry 3 , Far Cry 3: Blood Dragon , Far Cry 4 with minor variations).
~1–15 MB Purpose: Contains metadata for every audio asset inside the paired .dat . For reverse engineering, modding, or audio extraction, the
In Far Cry 3 , sound_english.dat and sound_english.fat act as the primary archive and index for English audio, utilizing the Dunia Engine’s file system. These files are used for language manipulation,, as replacing them allows for changing the game’s audio, and can be accessed or extracted using community tools like Gibbed Dunia2. For discussions on opening and working with these files, see the Steam Community thread . ~1–15 MB Purpose: Contains metadata for every audio