Exists lets you build playable 3D worlds from a text prompt

Most attempts at AI-generated virtual worlds give you one of two things: static 3D meshes that require hours of cleanup, or dreamy video diffusion clips that you can look at but cannot touch.

Tel Aviv-based startup Exists is taking a radically different approach. Today, the five-person team officially opened public access to its AI-powered 3D virtual world creation platform at exists.ai.

Anyone can now log in, type a single text prompt, and instantly step inside a fully generated, ready-to-explore 3D environment without touching a single line of code or modeling tool.

The public release follows a multi-month early access phase with thousands of users, which produced thousands of unique playable spaces while maintaining remarkably high engagement.

A world model inside Unreal Engine

At the core of Exists is a novel world model architecture that learns to generate inside a game engine, rather than treating generation as a standalone video diffusion problem.

The entire platform runs on a custom cloud-hosted fork of Unreal Engine. Because it operates within a real engine, the generated environments come out of the box with dynamic lighting, multiplayer networking support, and functional AI bots.

Exists CEO Yotam Hechtlinger, who holds an AI Ph.D. from Carnegie Mellon University, explained that the future of game AI lies in embedding game engines directly into the intelligence loop. The system understands not just visual aesthetics, but how a virtual space functions as a game.

Beyond Hechtlinger and his four core teammates, about 20 people have contributed to building the procedural systems, generative models, and interactive architecture behind the project.

From static sets to natural language gameplay

The company is not stopping at static environment generation. It is currently developing live Unreal Engine code generation capabilities.

Once deployed, this feature will allow creators to describe gameplay rules, logic, and entity behaviors in plain English, turning static scenery into interactive games on the fly.

For storytellers and educators who do not need playable mechanics, Exists also lets users export stylized video clips and cinematic camera sequences directly from their generated worlds, offering an instant alternative to traditional previs and 3D animation software.

Why it matters

For non-technical creators, educators, and hobbyists, Exists effectively removes the technical wall surrounding interactive 3D media. Building an interactive, multiplayer-ready space historically required specialized technical art and networking skills; reducing that entire pipeline to a text box makes rapid prototyping virtually frictionless.

Across the industry, this represents a smart counterpoint to the hype around pure video-based world simulators. Training end-to-end neural networks to simulate 3D physics from scratch is wildly expensive and notoriously prone to hallucinated collisions. We think leveraging a modified Unreal Engine underneath gives Exists an unfair advantage, letting established rendering, lighting, and networking systems handle the heavy lifting while the AI simply orchestrates the scene.

However, this architecture comes with clear challenges. Streaming dedicated cloud-based Unreal Engine instances to thousands of concurrent free users carries immense infrastructure costs. It remains to be seen whether Exists can maintain sustainable unit economics, and whether prompt-to-code generation will ever hold up for complex, bug-free game mechanics.