I get the impression that most MMOs are extremely messy with how they chuck files together.
I may be wrong, but I think PSO2 packs a lot of stuff into grouped archives.
If they make a minor change to one file, the whole archive needs to be updated.
And from extracting some of the files, they seem to have some duplicates as well.
So... that's probably why it's so big. Dupes + replacing existing archives instead of patching them.
Correct me if I'm wrong.
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