The single most important file for English text is local_en.pack . This is a compressed archive containing all in-game text: building descriptions, unit names, event messages, UI buttons, and tutorial scripts.
: Includes updated or patched text strings that override the base local_en.pack .
Unlike text files, you cannot simply copy someone else’s Voice_English.pack if your Steam account region differs. These files are sometimes encrypted with Steam’s CDN. Instead, use Steam’s "Verify Integrity of Game Files" (see below).