Repackers take the original game files (often 60GB+) and use advanced compression algorithms (like FreeArc or Zstandard) to shrink them down (sometimes to 15GB). When you run the installer, your CPU decompresses and rebuilds the original files on your hard drive.
The cardinal rule of piracy is the "Space-Time Trade-off." To download a game that is 5GB smaller, you must pay for it with time during installation. A Black Box repack could take 2 to 4 hours to decompress on a mid-range PC. Fans affectionately called this "the torture test," but in hindsight, watching a DOS-style progress bar move at a snail's pace was agonizing. blackbox games repack
Unlike many groups that "bust" due to legal action, Black Box simply faded away. Discontinuation: Repackers take the original game files (often 60GB+)
This is critical.