A fan-made project is bringing Halo 3 and Fallout: New Vegas together, allowing players to explore the Mojave Wasteland as Master Chief while using weapons and vehicles from the Halo series. The project, created by YouTube developer Reveries, aims to run both games simultaneously rather than rebuild either title from scratch.
Footage of the crossover shows Master Chief exploring the post-apocalyptic setting of Fallout: New Vegas with access to familiar Halo equipment, including the battle rifle, energy sword, grenades, and gravity hammer. The footage also features vehicles such as the Warthog and Covenant Banshee, allowing the Spartan to travel across the Mojave by land and air.
The project reportedly supports the full Fallout: New Vegas campaign, including its dialogue options. This would allow players to experience the role-playing game's story and conversations while controlling Master Chief and using Halo's combat mechanics.
Halo 3 and Fallout: New Vegas Run Together
The crossover is part of a growing collection of fan-made projects that combine established games in unexpected ways. Recent experiments have included recreating Minecraft inside Elden Ring, bringing Mario into Halo, and introducing elements of Skate into Call of Duty.
Many of these projects have drawn attention as AI-assisted development tools and so-called vibe coding make it easier to experiment with game mechanics and combine existing experiences. The Halo 3 and Fallout: New Vegas project follows a similar trend, although its developer has clarified that the work is not a rewrite or decompilation of either game.
According to Reveries, the project integrates the two games so that they can run simultaneously, bringing Halo's original gameplay into the Mojave. The developer has also cited Chasm's SkyCraft project as an inspiration.
The crossover remains in active development, with a release on GitHub planned for a future date. As a result, players cannot currently download and play the experience themselves, despite the footage demonstrating several of its features.
Xbox Labs and the Rise of AI-Assisted Game Projects
The project arrives as AI-assisted game development continues to attract attention across the gaming industry. Microsoft has also explored experimental projects through Xbox Labs, which has helped bring AI-driven gaming experiments into the wider conversation.
These developments have raised questions about how accessible game development could become as AI tools improve. Fan projects that previously required extensive technical knowledge may become easier to prototype, potentially allowing developers to test unusual combinations of game mechanics, characters, and environments.
However, the Halo 3 and Fallout: New Vegas crossover remains an unfinished project, and its planned release will determine how much of the experience can be made available to players.
For now, the footage offers a look at what happens when two very different games are combined. Halo 3's sci-fi weapons, vehicles, and combat mechanics appear alongside the dialogue-driven role-playing systems and post-apocalyptic world of Fallout: New Vegas.
Although the project is not yet playable, its planned GitHub release could give fans an opportunity to explore the crossover themselves once development progresses further.
