I’m drawing you an iceberg.
> custom archiving tools
> nextgen archiver for pirates that was never released
> random file dump has the code
> but there are no instructions how to build it
> but it’s useless anyway
> because apparently 7zip, rar, lzma is past century
> customly built unarc.dll
> third-party compression tools that the packer might or might not provide
> even if you have the tools the archive may be passworded
> then you have to hardcode your password into your own reverse-engineered setup for unarc.dll, build it then you can unpack others’ stuff
> provided that you know the password