A non-player character, or NPC, is any character in a video game who is not directly controlled by you, the player. It’s the zombie you shoot in the face in The Last of Us. It’s the innocent bystander you hit while speeding in Grand Theft Auto V. It’s the capitalist racoon who enslaves you into a lifetime of debt in Animal Crossing.
They are often characterised by a lack of agency and depth: a result of them being restricted by a set of pre-determined choices and algorithms. But artificial intelligence is getting smarter – and NPCs are too.
New movie Free Guy takes this to its most extreme conclusion, positing a scenario in which an NPC (played by Ryan Reynolds) gains self-awareness in a huge Grand Theft Auto-style video game. No longer is he a puppet with a set of stock phrases, but he can think, feel and interact. Surely this is the future of gaming?
“The chances of an NPC becoming self-aware are virtually zero,” says Dr Edward Powley, associate professor of artificial intelligence in Falmouth University’s Games Academy. “Creativity, consciousness, self-awareness – we might be able to create the illusion of some of these, but achieving them in any meaningful way is still decades away, partly because our understanding of how the human brain does these things is still very limited.”
But that doesn’t mean that game developers are not experimenting with AI. In 2020, game developer Ubisoft released Watch Dogs: Legion, which populated its dystopian recreation of London with some of the most dynamic and idiosyncratic NPCs ever seen.
To achieve this, they built Census, a complex system that generates biographies, relationships and narratives for the city’s NPCs population. Save a man from police brutality one day, and he and his brother may become your allies the next… or your enemies, if you accidentally injure their best friend in a firefight.
In terms of the future, the tech that Powley is most interested in is natural language processing. “This is behind systems such as Alexa and Siri, which allows you to interact with a computer system using plain English.” The potential for video games is reactive NPCs who can hold a real-time conversation with the player as they type sentences or speak into a microphone.
The most cutting-edge example so far is 2005 video game Façade, in which the player has to navigate a cocktail party without saying the wrong thing and being thrown out. “The technology needs to advance further to be truly feasible in games,” says Powley.
There is a risk that such technology could compromise authorial control. This is Powley’s concern with methods such as machine learning, which allow AI to analyse data, interpret it, and make its own decisions.
This could lead to NPCs who behave with more freedom and flexibility. But leaving aside the fact that it would require a lot of time and computational power, there’s also the question of whether ‘better’ NPCs would make for better video games.
“Video games are all about telling a story or giving the player an experience, and NPCs being too unpredictable can break that,” says Powley. “A lot of what we do when we play games is about figuring out systems, and NPCs that are too unpredictable are too difficult to figure out.”
Verdict: While intriguing, the AI underlining Free Guy is neither possible nor desirable.
About our expert, Dr Edward Powley
Edward is an associate professor in the Games Academy at Falmouth University. His research focuses on artificial intelligence in video games, particularly on developing general-purpose AI methods which can play a wide variety of games. He is also an independent video game developer.
Read more from Popcorn Science: