First it listens. A good PK2 extractor sniffs the binary seam—headers and magic numbers—then maps the interior world: file offsets like streets, pointers like alleys. It doesn’t guess; it counts, decodes, and always verifies. A misread length field is an invitation to chaos: truncated textures, corrupted models, a chorus of missing polygons. So the extractor builds a ledger: entry name, offset, size, flags, checksum. Each row is a promise.