During Summer Game Fest 2025, Atomic Heart developer Mundfish also unveiled a new project called The CUBE. It still takes place in the same setting as the original game and the freshly announced sequel , but it will be a much different game: an MMORPG shooter.

The developers are trying to mix unique worldbuilding, an intriguing narrative, and exciting quests into one game. The goal is to create a living world full of memorable characters, diverse biomes, and tons of enemies, including powerful bosses. The backstory is that a giant cube appeared in the sky and players will have to scour its ever-shifting environments and mysteries.

Robert Bagratuni, Founder and CEO of Mundfish, said in a statement:

At Mundfish, we were the first in the industry to implement a technology that allows thousands of objects to move and rotate simultaneously across massive stretches of terrain — online and in real time. No other game has ever done this before. This became possible thanks to our innovative proprietary split-rendering system, which redefines how motion is handled in interactive environments. The technology delivers maximum performance even under extreme load. In The CUBE, physics, ballistics, and gravity feel completely natural — but under the hood, it’s powered by rocket science. The system enables seamless transitions, precise object tracking, and synchronized multiplayer in a living, ever-evolving world. It’s a true technological breakthrough.

The CUBE has no release date yet, but given the genre, it might take a while. Meanwhile, you can already to your Steam wishlist. The game is also being developed for consoles, by the way.