When a spell of strong wind swept through northern China last weekend, most people hunkered down indoors, riding out the weather with shows, snacks, and games. At the 36Kr gaming desk, the buzz was about one particular title: InZoi, a new life simulation game that wears its Sims inspiration proudly but pushes the genre into deeper, weirder territory—thanks to artificial intelligence.
But before diving into virtual real estate and digitally scheduled date nights, a larger question loomed: can AI create? It’s a debate that has grown louder in the last two years—and InZoi throws fuel on the fire.
One camp argues that creativity requires emotion and experience, something machines don’t have. The other suggests: if AI doesn’t understand human life, why not let it live one—digitally?
For years, the idea was easy to laugh off. Where would such a world even exist?
Maybe now, it does.
A jolt to a stale genre
Released on March 28, InZoi is catching attention not just for its detailed cityscapes or customizable avatars, but for its integration of generative AI to power non-playable characters (NPCs). The goal? Make them act less like background extras and more like people.
“I was trying to matchmake two Zois, but one of them suddenly quit their job to go backpacking, and the other got hooked on stock trading—so much for my love story,” one player told 36Kr. In InZoi, characters are known as Zois.
An InZoi developer echoed this unpredictability:
“We didn’t want NPCs that just repeat scripts. They should have real emotions—like actual people.”
It’s a swing at innovation in a space where things have long been stagnant. Last September, EA announced it wouldn’t be releasing The Sims 5 anytime soon. That left a vacuum in a genre long monopolized by one franchise.
But the void didn’t last long. In stepped InZoi, which climbed to the top of Steam’s wishlist charts even before its release. On launch day, more than 80,000 players logged in simultaneously, lifting the game into the platform’s upper ranks. Since then, over 10,000 reviews have poured in, of which roughly 82% of them are positive.
That kind of traction is rare in a genre long dominated by a single heavyweight. Life simulation games have been so thoroughly defined by The Sims that the category itself feels synonymous with the franchise.
Since its 1999 debut, EA’s The Sims has set the benchmark with four mainline entries and over 90 downloadable content packs for The Sims 4 alone. To buy into the full experience today would cost upwards of RMB 1,000 (USD 140).
Few competitors have made it past the starting line. Paradox Interactive’s Life By You was shelved in June 2024 after repeated delays. Meanwhile, Paralives, a crowdfunded indie project unveiled six years ago, is still inching toward an early access release in 2025, though whether that will actually happen remains anyone’s guess.
How InZoi weaves AI into gameplay
To stand out, InZoi bet big on embedding AI across the board—especially in its “Smart Zoi” system, powered by Nvidia’s ACE technology.
Rather than giving NPCs set routines or lines, Smart Zoi enables characters to develop goals, form relationships, and adapt to their environments. An extrovert might rush to help a neighbor; an introvert might quietly walk away. Their behavior changes depending on the time of day, social context, or recent events.
According to the developers, Smart Zoi operates on four main axes:
- Dynamic behavior: NPCs have distinct personality traits, motivations, and life goals. Their routines shift with changing circumstances, like time of day or life events, and interactions with players can influence future actions. For instance, a single player choice could lead to a change in an NPC’s lifestyle.
- Social simulation: These characters work, socialize, shop, and take part in community events. They can also be folded into player-created storylines, mirroring the social complexity of real urban life.
- Generative storytelling: AI-powered narratives ensure each player has a unique experience. Different NPCs generate different arcs and events, continually shaping the world around them.
- Natural dialogue: Players can have natural conversations with NPCs like they would with a chatbot, and receive relevant, often surprising, responses.
“With Nvidia’s technology, we wanted to give players a new way to view and shape city life—to really live in the world they build,” one developer said.
You can turn Smart Zoi on or off. When it’s active, NPCs consider everything from household income to romantic tension when making decisions. One might skip lunch to catch a museum exhibit, and the system will even tag this as an “exception,” complete with in-game reasoning.
In some cases, the emotional nuance can be startling. In one Bilibili test video, an NPC family seemed off—frequent fights, no jobs, visibly distressed child. It turned out they were grieving a lost child.
InZoi doesn’t just simulate. It lets you play puppet master. With a tool called the “Zoi Pen,” players can assign characters specific goals by typing short instructions. Tell one NPC to chase a Hollywood dream, and that becomes its life goal. Instruct another to pick fights for no reason, and it’ll gladly take up the role of neighborhood menace.
GPU meltdown and mood swings
For all its ambition, Smart Zoi doesn’t come cheap. It’s a resource hog, and its complexity can push even high-end hardware to the brink.
On top-tier setups with RTX 5080 cards, frame rates reportedly drop from 120 to 45 when the feature is switched on, according to 36Kr. On mid-end rigs like the RTX 3070, crowded scenes can at times devolve into jagged slideshow nightmares. Even players running RTX 4090Bs—the cream of the crop—have reportedly seen frame rates sink below 20 FPS. No wonder InZoi has earned the nickname “GPU killer” on Bilibili.
Some settings let players dial down Smart Zoi’s load, limiting it to on-screen characters or capping the queue size. Early reports, however, suggest the performance hit remains significant.
Then there’s the emotional logic. NPCs can swing from joy to rage without warning. One reviewer watched a character go nuclear after stepping in a puddle. Emotional realism? Not quite.
Much of that unpredictability stems from Krafton’s proprietary gaming small language model (GSLM), a lightweight, locally run alternative to cloud-based large language models (LLMs) used by platforms like ChatGPT and DeepSeek. Built to avoid lag and server dependencies, GSLM powers everything from Smart Zoi to Psycat, the in-game feline assistant that fields player questions.
InZoi might be the first game to fully run a system like this on local devices, and that ambition comes through. So do the cracks. Still, even when things go off the rails, the promise of what AI could bring to gaming is hard to miss.
What’s next?
When ENIAC, the world’s first general-purpose computer, debuted in 1946, it filled a room and weighed 30 tons. Now, a smartphone in your pocket is vastly more powerful.
Tech history follows a pattern: things shrink, become accessible, and eventually feel indispensable. InZoi may be clunky, demanding, and rough in parts—but it signals where gaming might go next.
If AI can move beyond simulating life to actually experiencing and reacting to it, then we might not be that far from digital consciousness—or at least to characters that behave with unsettling realism. What happens then, when your NPC becomes more interesting than you?
That’s a question for another rainy weekend.
KrASIA Connection features translated and adapted content that was originally published by 36Kr. This article was written by Liu Chongjiang for 36Kr.