Some websites offer a one-click "Blur English Patch.exe." These are high-risk for malware, keyloggers, or cryptocurrency miners. Always choose manual file replacement ( .loc , .reg , .bin files).
The patch replaces the Russian.pck (or equivalent) with the English.pck file. This updates the UI, subtitles, and menu prompts.
This is usually coincidental. However, some repacks install a "loose file" patch that makes the engine load slower. To fix, use Gibbed's Blur Tools to repack the loose files into a .blx archive. This is advanced; only do this if you have stuttering.