Again a really honest shooter

So I need a game about once a year. A shooter with no frills, which focuses on good single-player gameplay and thus holds up to the end in good spirits. Of course, one does not have the time or the game replayability, the offers a herrkömliche any multiplayer, but it's after that, I also do not look at a game like this. In such a game, it is the 50 for 15-20 hours of gameplay worth it!