If you boot up the "J Z64" version expecting a simple translation swap, you are in for a surprise. Nintendo of Japan made significant code changes that affect gameplay:
The Chain Chomp uses a unique barking sound that resembles a person saying "wanwan" (the Japanese onomatopoeia for a bark) instead of a realistic dog bark. Why Speedrunners Prefer the "J" Version
Most emulator-based modding, such as the SM64 Plus Installer or decompilation projects, requires a pristine .z64 file to work correctly. Technical Details: Loading sm64.z64
