A toadstool, the Universe, King Midas, the Golem. This is not a free association exercise, but rather a list of concoctions my coworkers and I have produced in Infinite Craft, a deceptively simple browser game by developer Neal Agarwal, who you may know for creating a delightfully “unhinged browser game about passwords” last year.

Infinite Craft resembles earlier combination games like Little Alchemy or Doodle God, asking you to drag to combine two elements together on a big whiteboard in order to unlock new, ever more complex materials to work with. Like those earlier games, it starts out pretty bare, with your craftables limited to the four classical elements of fire, earth, air, and water, represented here by little flash cards with emojis. 

The difference in Infinite Craft is that it uses generative AI to introduce reactivity and experimentation in its responses, rather than a puzzle-solving ethos with set combinations like in prior games. “I think Doodle God is one of the first games I downloaded on my iPhone when I was a kid,” Agarwal informed me over email, noting that “Other games in the genre play a bit more like puzzle games, whereas I think this is more of an open-ended sandbox game.”

The starting elements lead to pretty tame results like forming plants from earth and water, then maybe fossils from stone and plants. But the fact that there are few wrong answers causes things to quickly spiral out of control into philosophical concepts or pop culture characters.

I’m still jealous of how PC Gamer executive editor Tyler Wilde managed to produce Yoda out of the Tao and a Yeti⁠—it makes a weird kind of sense, too, with Yetis being furry hermit guys like Yoda and George Lucas almost certainly having borrowed from Taoism among other philosophies in Star Wars’ cultural slurry, but I don’t think the LLM Agarwal used was thinking about it on that level. Tyler was subsequently able to match Yoda with Yin and Yang to produce the decidedly less thought-provoking “Yin-Yoda.”

Anyway, I got Yetis down in my game, but Laozi’s Way continues to elude me, and my quest for it led to the creation of Genius, the Universe, the Big Bang, and God⁠—I feel like some kind of philosophical revelation may have just shot over my head?

Spiritual enlightenment aside, we were curious just how this thing works. “I’m using the latest Llama 2 LLM from Facebook on the backend.” Agarwal explained. “Every time someone tries to craft something novel, I ask Llama 2 with a prompt what the result should be.” On the novelty front, brand-new results like PCG senior editor Chris Livingston’s “Rice Krispie Trees” get a shiny “First Discovery” indicator on them.

Though Agarwal noted that Llama 2 is “not quite as smart” as ChatGPT and gave him some trouble when it came to figuring out the right prompt and examples, the programmer said that the models are improving at a rapid clip and that these advancements will trickle down into later versions of the game.

I’m pretty distrustful of AI tools in general, but I and other AI-skeptical members of PCG were immediately charmed by Infinite Craft. Agarwal has his own hesitations about AI as well: “I see both sides of the debate, I think artists should definitely have more control over who gets to use their work to train models.” But the programmer thinks Infinite Craft is only the beginning  when it comes to creative applications of AI in games, calling it “just the simplest AI game I could think of that wouldn’t bankrupt me.

“You can imagine a 3D Minecraft version where you can really create anything you want. We’re not there yet⁠—but I’m really excited to see more experiments in this space.”

In the meantime, Agarwal was caught off-guard by how quickly Infinite Craft blew up on Twitter, quickly petitioning host Together AI to get more bandwidth for the project. “I was actually hoping this game would be more of a slow takeoff compared to The Password Game since it uses so many relatively new technologies and things will definitely break,” Agarwal said of the game’s rapid popularity. “It’s been a struggle keeping the servers up so far.” You can check out Infinite Craft, as well as Agarwal’s other games over on Neal.fun.