TECH NEWS – The first major result of the historic collaboration between Unity and Epic Games has allowed a Unity-developed game to run in real time within an Unreal Engine environment. The demonstration was not a simple technical trick, but a fully functional integration in which physics, lighting, controls, and interactions remained synchronized between the two engines.
When Unreal Engine 6 was announced, Tim Sweeney argued that the future of the graphics engine would lie in a collaborative ecosystem where all the major video game companies could work together, ultimately enriching Fortnite with new experiences. Although Unreal Engine 6 will not arrive until 2027, the CEO of Epic Games has already completed the first step of his master plan, or rather, Unity has completed it for him. The company behind the Unity graphics engine has successfully run a game developed with its own technology natively within an Unreal Engine environment.
The trajectories of Unity and Epic Games have been very different over the years, to say the least. While Epic has captured a substantial share of the industry and currently has dozens of top-tier studios developing games with various versions of Unreal Engine, Unity went through a genuine ordeal that reached its peak in 2023. The company, then led by John Riccitiello, the former CEO of EA and later Unity, announced a fee that would have forced developers to pay for every installation of a game created with the engine. The decision turned the company upside down and provoked such intense backlash that Unity reversed course only days later.
After reaching one of the lowest points in its history, Unity gradually recovered and announced a partnership with Epic Games in November 2025 to bring Unity-developed games into Fortnite as experiences within its metaverse. As part of that collaboration, Unity demonstrated at Unite Seoul 2026 how Fantasy Kingdom, a project developed with its own engine, could run in real time through Unreal Engine. According to James Stone, Unity’s senior director of technical product management, this was not a technical trick but a fully functional integration: the game was simulated in Unity while Unreal Engine handled the rendering, with every system synchronized between the two environments.
Stone emphasized that the technology went far beyond what viewers could simply see on the screen. During the demonstration, an Unreal Engine character moved through a scene created in Unity while physics, lighting, controls, and interactions operated together in real time. “What you’re seeing here is a game simulated in Unity, rendered with Unreal. This isn’t smoke and mirrors. Everything happens in real time. But it’s not just about the rendering. Look at the avatar. It’s an Unreal character moving through a Unity world. Physics, lighting, controls… Everything is synchronized between both engines,” Stone explained.
Epic Games CEO Tim Sweeney Celebrated the Demonstration as a Victory
Tim Sweeney naturally joined the conversation as well. The head of Epic Games reacted on social media with a short but forceful message: “Connect all the engines!” The executive has long advocated for an ecosystem in which game engines, content, economies, and social features can interoperate across different platforms and video games. “The industry should come to the conclusion that the value of connecting everything is greater than the value of remaining separate,” Sweeney told PC Gamer in June.
Beyond the demonstration, Unity also used the event to announce Unity 7, the next version of its graphics engine, which is scheduled for release in 2027. The new version will introduce improvements to rendering, monetization, and collaboration tools, along with a protocol designed to connect programming agents based on generative artificial intelligence. Early access to the official Unity integration with Fortnite will also arrive that year, while the first preview versions of Unreal Engine 6 are expected by the end of 2027.
Source: 3DJuegos
