At the turn of the 1980s, most PC adventure games were played using only the keyboard. In those days, adventure games didn't use action menus like more modern games, but simply presented the player with a command line where they could freely input text to decide the actions that characters would take and proceed through the story. Free text input systems like these allowed players to feel a great deal of freedom. However, they did come with one common source of frustration: players knowing what action they wanted to perform but being unable to do so because they could not find the right wording. This problem was caused by the limitations of PC performance and NLP technology of the time.

40 years have passed since then, and PC performance has drastically improved, as have the capabilities of NLP technology. Using "The Portopia Serial Murder Case" as a test case, we'd like to show you the capabilities of modern NLP and the impact it can have on adventure games, as well as deepen your understanding of NLP technologies.