Bioshock Infinite: The Future of NPCs

When Ken Levine speaks, people listen.  After getting a flurry of high praise reviews, the creative director and co-founder of Irrational games can say that he is chiefly responsible for two of the greatest games in this console generation.  The desire to hear the creative mind behind System Shock 2, Bioshock, and Bioshock Infinite was obvious as the line to Levine’s PAX East panel on creative process behind Bioshock Infinte’s female protagonist, Elizabeth, started 9AM Saturday morning, nearly three hours before the talk was scheduled to start.

I sat in the back of the hall during the talk, not sure what I was going to hear but conscious of the fact that I would be playing Levine’s latest success this upcoming week and eager to learn all I could about the game.  Levine used the panel as an opportunity to talk about the AI Irrational had created for it’s lead female character in Bioshock Infinite.  I considered leaving, I had a few appointments to keep and other panels to see, I was not sure how much I wanted to hear about such a narrow aspect of Irrational’s new title.  But then I remembered the number one rule, when Ken Levine talks, you listen.

Levin talked about how in System Shock 2 Irrational had started a journey, developing AI interaction with SHODAN, an artificial intelligence with a taste for destruction.  At one point in System Shock 2 the player is confronted with a choice of going through a door. SHODAN does not want the player to find what is behind the door and uses threatening language to discourage the player.  If the player goes through the door SHODAN would punish them by withholding upgrades, however if they don’t go through the door SHODAN would reward them with more upgrades.  The process of programming AI with a mission to stop the player, using dialogue and motives rather than actual force, was the first step for Irrational toward creating a smarter non-playable character.

The process of creating better AI continues as part of Irrational’s legacy with Bioshock, in the relationship between the Little Sisters and the Big Daddies.  Levine has revealed multiple times that this relationship was the most problematic in the game and left the team at Irrational wondering if the eerie duo needed to be cut. Creating two characters that would be aware of their intrinsic relationship to each other was difficult to program, however proved to be one of the most powerful aspects of the game.  Big Daddies and Little Sisters have become an iconic relationship in video games because of the way the two characters interacted with each other.  Whether it is the Little Sister calling the Big Daddy, “Mr. Bubbles” or the fierce protectiveness shown by the armored mutant, the two creatures etch themselves into the player’s mind.

However, with Bioshock Infinite the goal was not to create an omnipresent AI that would work against you, or a symbiotic relationship between two NPCs.  The goal was to make a companion character that would travel with the player and assist them on their journey, both mechanically and emotionally.  This idea was embodied in the character Elizabeth.

The most impressive thing about Elizabeth — and there are quite a few — is the size of the team that it took to make her.  The PAX East panel was made up of the five members of the the team that built Elizabeth, consisting of voice actor, motion capture actor, writer, designer, and programmer.  This team worked to create a character that lived and breathed in the world around you, not simply in cutscenes.  They wanted Elizabeth to have her own ticks, her own ideas, her own curiosity, not simply to respond to the player.

This required a highly involved process, which Levine began breaking down by pointing to the characters voice, lent to her by actress Courtnee Draper.  Draper described the emotional process of creating the character, working in a room with Levine and male counterpart Troy Baker, as she would desperately attempt to convey the voice of Elizabeth.  The second actress required to bring Elizabeth to life was Heather Gordon who gave Elizabeth her body. Gordon explained the difficult process of creating a character which already had a voice; slavishly doing take after take, while hitting specific actions with her body to match Draper’s dialogue.  Often voice actors get to take a lot of credit but they are not only thespians involved in creating a character, and Gordon’s work deserves recognition.

Then came the work of Amanda Jeffery and John Abercrombie who wrapped the performances of Gordon and Draper in heightened animation and provided the coding to make Elizabeth act more like a human and less like a robot. This involved recoding everything in Bioshock Infinite so that Elizabeth would recognize it as something she should be interested in and interacting with.  After they built the AI, they created animations so that she could respond to these things individually.  Combining all of these ingredients was a difficult process that led to Elizabeth being on the cutting room floor numerous times.  But after some success, the team at Irrational were able to bring Elizabeth to life and stopped calling her by her full name, casually referring to as, “Liz” like she was someone they knew.

The PAX East panel has been on my mind for some time now.  It made me think about the time I spent with the demo for The Last of Us, and though the AI of Tess and Ellie did not stand out when I first played it, how would I feel after experiencing the specific details of Elizabeth?  How would creating a character with such depth change the perceptions of AI in the industry?  People often think about the future of games meaning more photorealism and expanded controls, but in all honesty wouldn’t it be more important to emphasize smarter games?  It is inspiring to see Irrational taking this challenge head on.

When I tore off the plastic wrapping of my Bioshock Infinite copy, popped out the disc, and loaded it in the tray of Xbox 360, I couldn’t help but have expectations of what Elizabeth would be.  Levine and “Team Liz” (as they have coined themselves) had drawn my attention to the character and I feared they had raised my expectations too high.  But I was pleasantly surprised to find that it only improved my appreciation of the character.  Elizabeth’s personality shines through, making her a character easy to care for.  It is important to note that her features have been heightened to make her emotions easier to read, her eyes are bigger, her lips are fuller, her face communicates feelings her dialogue doesn’t have to.  I find myself watching her when we enter a room to see how she responds and reacts.  She will run when she’s scared, she will pause when intrigued, and will help you when it is needed.  Compared to the air-shooting companions in Resident Evil and most military shooters, Elizabeth is a rocket scientist.

There are many interesting things about Bioshock Infinite, many things that the game did well and a couple choices that could argued about.  But it is clear that Irrational’s vision of creating a character that feels alive was a success.  People have been praising the character of Elizabeth left and right.  It just goes to show, when Ken Levine talks, you listen.