It seems like 4A Games and Deep Silver missed this loophole. According to InkBubble, a user on Reddit, Metro: Last Light can be easily tweaked via the registry to enable you to play in this ‘hardcore’ mode of the game.
This might be a bit embarrassing for the respected companies responsible for such a great game but free stuff are always welcomed.
To enable ranger in full functionality, simply follow the next guide.
“1: open regedit
2: Navigate to HKEY_CURRENT_USER/Software/Valve/Steam/Apps/43160 – or any other folder you might find Metro: Last Light in it
3: Create a new String value called ListOfInstalledDLC with Value data 222801
4: Open game – New game – Select Hard Ranger Mode”