Version 1.138 is the last version fully compatible with these acclaimed mods:
If you already own the game but cannot find your key, use these platform-specific methods: Right-click the game in your Steam Library , and then click Alternatively, open the Steam Overlay (Shift+Tab) while the game is running to view the key. Log in to your GOG profile , click on the title, and select Serial Keys Windows Registry , and navigate to mount blade with fire and sword 1.138 serial key
Once you have your 16-character (4x4) or 25-character (5x5) key, use one of these activation paths: Standard Activation Version 1
Q: How do I know if my Mount Blade with Fire and Sword 1.138 serial key is genuine? A: Ensure that you purchase the game from authorized retailers, and verify the serial key with the game developer or retailer if you encounter any issues. and then click Alternatively