How cheerful and fun it still feels! I'm really surprised how id Software in 1994 not only literally created the genre, but also immediately gave it just a reference lesson in level design, which is the first chapter. In the second and third they start to experiment and the results vary, but it is still very high quality, very easy to understand at first and quite difficult towards the end. Small details like the swinging of weapons when walking, the face of the main character at the bottom of the screen, secrets in levels that often trick you at the same time, or interesting design solutions so easily raise the cult status of this game years later. Did Carmack, Romero and company know that they were creating such a cult project then? I don’t know if there is an exact answer to this question, but I think that they definitely knew that dynamically destroying demons with a lot of blood and a cheerful soundtrack would be a fun experience. And in this they were absolutely right.