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Facade is one of the most unique and novel games of its kind: a real-time interactive drama where players communicate directly with non-player characters in a short dramatic scenario. While over 15 years old, the game is one of the rare cases of an academic research project that achieved global status and popularity. With exposure in mainstream press, award recognition and a cult status on the internet as popular YouTubers run lets plays through its quirky and occassionally awkward drama.
In this AI and Games case study, we’re going to take a look at how Facade works. The years of research and development required to make it happen and how every layer of the games AI systems had to be invented, in order to make it work.
About Facade
In Facade players are invited to the apartment of Grace and Trip: a married couple who met courtesy of the player character back in college. However, things aren’t going so well in their relationship and your coming round for drinks that evening is the make-or-break moment for their marriage. You are unwittingly dragged into passive-aggressive psychological head games as the couple lash out at one another about their hobbies, their career choices, their families, their sex life and much more.
Players interact with the couple by wandering through their apartment and interacting with objects and furniture around the house, or by chatting with them directly. What makes Facade stand out from so many other games is that you are talk to Grace and Trip by typing into the keyboard and the characters interpret your inputs and respond accordingly. They react with elation, surprise, laughter, disgust or even anger as you challenge their points of view, compliment them on their decisions, ask them about issues they don’t want to discuss or just outright insult them.
Ultimately depending on your actions, the game will result in one of several pre-defined endings. If you help the couple navigate their issues successfully, their love for one another is rekindled and they politely ask you to leave. However, like in real life, this is a difficult process to navigate and can easily slip into one of the many bad endings. Players can be ejected from the house for their treatment of the couple or other antisocial behaviour, with Trip forcing you out the door. In fact you can even have Trip slam the door in your face at the very beginning if you successfully insult him. You can even ignore the drama that awaits and simply turn around and get back in the elevator. However, the remaining bad endings arise from your continued discussions with the couple, where Grace can decide to leave Trip or vice versa, or potentially being told to leave after nothing is resolved, only for the couple to continue to bicker and argue after you’ve left the apartment.
Facade is well-known in the YouTube ‘let’s play’ community.
Facade is well-known in the YouTube ‘let’s play’ community.
Facade holds a special place in game AI history: a research project that achieved cult status! A quirky and eclectic game that stands out as one of the most novel applications of its time. Creating this exciting and dramatically rich environment where players can interact with and shape the story as it happens. Resulting in the game being downloaded over 5 million times since its release in 2005 – and I suspect that number is dire need of an update. But despite its success, the game is most certainly more famous for when it goes wrong thanks to the agency given to the player. In the past 10 years Facade has become infamous within YouTube and the let’s plays community, with high profile creators garnering millions upon millions of views for their playthroughs of the game. It’s ability to react – or fail to adjust – to player behaviour ranging from the perfectly normal to the completely irrational makes for great comedic fodder. Its cult status means that many people are not aware of its AI research origins and know it purely for the meme fodder it generates. But the game is but an early chapter in the larger story of its developers, seeking to create a fully interactive drama and the one big step forward taken in making that a reality.
Andrew Stern
Michael Mateas
Facade was developed by two people: Andrew Stern and Michael Matteas. Before the game began production, Stern was a game developer and designer at PF.Magic in San Francisco and had worked on several entries of the highly popular Petz series. Meanwhile Matteas was a PhD candidate at Carnegie Mellon University and his early research at that time had been around building physical and digital avatars that expressed some form of intelligence that could build emotional connections with human users. Both were interested in the idea of autonomous interactive characters and systems each in their own way. This led to Stern attending AI research conferences, and ultimately the pair crossed paths. Their mutual interest in intelligent avatars led them to pursue the next step, intelligent actors and the formation of the interactive drama.
In 1998, emerging from a hot tub at a conference in Snowbird, Utah, Mateas and Stern decided to collaborate. “As Andrew and I talked,” Mateas recalls, “we sort of egged each other on to jump as far out of the mainstream as possible.” They resolved to create a game that would put a not in front of every convention of today’s video-game industry. They looked upon their game as a research project and figured that building it would take two years. It took more than five. Now they are starting on a larger version, this time a commercial game.
“Sex Lies and Videogames”
Jonathan Rauch, Atlantic Unbound, November 2006
Their passion project was a labour of love with no budget to speak of and pair worked on it around other projects – with Matteas a grad student and Stern working self employed. The 5 years of development included 3 years spent authoring the drama itself, plus over 5 hours of recorded dialogue for Grace and Trip provided by actors. Despite this herculean effort, the team achieved only around 30% of what they had originally envisioned. But that was more than enough to make an impression.
Released for free on Windows XP in 2005, with a MacOS version in 2006, Facade became one of the most famous and successful projects of its kind. Having previously been a finalist at the 2004 Independent Games Festival, the game subsqeuently won the Grand Jury prize at the Slamdance Independent Games Festival in 2006. With both Stern and Matteas garnering significant exposure with articles written about the game in the Atlantic, the New York Times and the Guardian. Meanwhile numerous academic publications in journals, conferences and books have been published discussing the design, development and processes behind the game itself. Not to mention all the YouTube walkthroughs, guides and jokes that have accumulated millions of views over the years.
But how does it all work? Well in order to really understand what Facade is doing under the hood, we need to take a look at a number of connected but distinct elements of the game.
How the game is structured and designed to achieve the original design goals while providing interesting challenges for AI to tackle.
Then we need to look at how AI is employed throughout the game to help craft the drama, and all the different subsystems, this includes…
A natural language processing and understanding layer for reading and translating the players inputs from the keyboard.
A drama management system that breaks up the story into dramatic beats, allowing it to change shape and adapt to events as they happen.
A behaviour language system that allows Grace and Trip to act as performers in the story, achieving the dramatic arcs set out by drama manager and reacting to player interaction.
How Facade Is Designed
At the time Facade started development, the idea of interactive story-driven was still very much in its infancy. While story branching and interaction systems already existed in the likes of point and click adventure games and some RPGs, Facade sought to achieve a high level of agency. Where the player could have a substantial impact on how the story plays out. Even now in 2020, games where players have a huge impact on the story are still relatively unique. Even series lauded for their story telling and character interactions such as The Walking Dead or Mass Effect don’t provide the player with much influence over the story, but rather different paths within it they can take based upon criteria being met.
Facade was designed with the intention of crafting a character-rich plot that based upon your interactions and conversations with the other characters, it would either immediately or gradually influence how the game pans out. To achieve this, the player is secretly playing along in several of what are known as ‘social games’. These social games are specific phases of Facade where based upon your interactions, they can influence Grace and Trip’s feelings on a particular subject matter, their self-awareness about their underlying problems and their affinity towards the player. Every provocation, criticism or praise found within the natural language typed in from the keyboard will nudge the characters feelings on each subject. All the while the game is monitoring the tension between Grace, Tripp and the player. All of this can influence the story beats that play out, how a character responds at a particular point in time and ultimately, which ending is reached in the drama. It’s important to recognise that Grace and Trip are essentially actors, where instead of learning specific stage directions or cues for a rehearsed play, they’re effectively improvising in real-time as an AI stage director is putting together the play in real time. However, while it’s being improvised on the fly, their performances are all pre-built and are designed to work in specific circumstances. And the underlying challenge the two actors face is in working together in real-time to ensure those pieces are put together correctly and ensure each story beat plays out successfully.
To help structure this and balance out how specific topics are explored or provoked, each playthrough of Facade is broken up into two main social games: the Affinity Game and the Therapy Game. The affinity game is where the system tries to determine whose side the player is on. This is actually also running another social game within called referred to by the developers as the ‘Hot Button Game
