Inworld wants to make this type of interaction more polished. It’s offering a product for AAA game studios in which developers can create the brains of an AI NPC that can be then imported into their game. Developers use the company’s “Inworld Studio” to generate their NPC. For example, they can fill out a core description that sketches the character’s personality, including likes and dislikes, motivations, or useful backstory. Sliders let you set levels of traits such as introversion or extroversion, insecurity or confidence. And you can also use free text to make the character drunk, aggressive, prone to exaggeration—pretty much anything.
Developers can also add descriptions of how their character speaks, including examples of commonly used phrases that Inworld’s various AI models, including LLMs, then spin into dialogue in keeping with the character.
“Because there’s such reliance on a lot of labor-intensive scripting, it’s hard to get characters to handle a wide variety of ways a scenario might play out, especially as games become more and more open-ended.”
Jeff Orkin, founder, Bitpart
Game designers can also plug other information into the system: what the character knows and doesn’t know about the world (no Taylor Swift references in a medieval battle game, ideally) and any relevant safety guardrails (does your character curse or not?). Narrative controls will let the developers make sure the NPC is sticking to the story and isn’t wandering wildly off-base in its conversation. The idea is that the characters can then be imported into video-game graphics engines like Unity or Unreal Engine to add a body and features. Inworld is collaborating with the text-to-voice startup ElevenLabs to add natural-sounding voices.
Inworld’s tech hasn’t appeared in any AAA games yet, but at the Game Developers Conference (GDC) in San Francisco in March 2024, the firm unveiled an early demo with Nvidia that showcased some of what will be possible. In Covert Protocol, each player operates as a private detective who must solve a case using input from the various in-game NPCs. Also at the GDC, Inworld unveiled a demo called NEO NPC that it had worked on with Ubisoft. In NEO NPC, a player could freely interact with NPCs using voice-to-text software and use conversation to develop a deeper relationship with them.
LLMs give us the chance to make games more dynamic, says Jeff Orkin, founder of Bitpart, a new startup that also aims to create entire casts of LLM-powered NPCs that can be imported into games. “Because there’s such reliance on a lot of labor-intensive scripting, it’s hard to get characters to handle a wide variety of ways a scenario might play out, especially as games become more and more open-ended,” he says.
Bitpart’s approach is in part inspired by Orkin’s PhD research at MIT’s Media Lab. There, he trained AIs to role-play social situations using game-play logs of humans doing the same things with each other in multiplayer games.
Bitpart’s casts of characters are trained using a large language model and then fine-tuned in a way that means the in-game interactions are not entirely open-ended and infinite. Instead, the company uses an LLM and other tools to generate a script covering a range of possible interactions, and then a human game designer will select some. Orkin describes the process as authoring the Lego bricks of the interaction. An in-game algorithm searches out specific bricks to string them together at the appropriate time.
Bitpart’s approach could create some delightful in-game moments. In a restaurant, for example, you might ask a waiter for something, but the bartender might overhear and join in. Bitpart’s AI currently works with Roblox. Orkin says the company is now running trials with AAA game studios, although he won’t yet say which ones.