“Boom, headshot” is widely associated with FPS Doug, a character from the internet series Pure Pwnage that became popular in the mid-2000s. The line spread through gaming forums, early video platforms and montage culture, then stuck around as a reusable reaction clip for precise hits and exaggerated victories. It is still common in shooter edits because the phrase is short, instantly recognizable and easy to sync with gameplay moments, much like the dramatic sting of the Inception Button in older meme editing styles.