How AI Agents Rebuilt Modern Warfare 2—and What Happened Next

Maurice Heumann’s AI-assisted Call of Duty: Modern Warfare 2 project set out to reconstruct the 2009 PC game as C++ code. By September 30, 2026, he said the game was playable and nearly free of visible bugs. Soon afterward, a video he had posted was disabled following a copyright-owner report, and news reports said the site hosting the code was inaccessible. The available reporting does not establish that Activision formally shut down the entire project. 20242526

How the decompilation worked

Decompilation works backward from a compiled program to produce code that people can inspect. Heumann’s goal was to recreate Modern Warfare 2 in C++ as closely as possible to the original, while making adjustments where useful. 1820

His initial setup used four Claude-powered agents: three worked on separate game systems, while a fourth oversaw the process and reviewed commits. The agents contributed to a shared code branch. 20 By September 30, Heumann said 17 agents were working in parallel. 26

This was a reconstruction effort, not simply a new game inspired by Modern Warfare 2. Heumann described the aim as recovering the original game’s code and functionality. 2027

From early progress to a playable game

The project’s reported progress changed over time. In late August, Heumann said about 80% of the game was decompiled but described serious problems, including a broken scripting system. 28 By September 30, he said the game was fully playable, most visible bugs were fixed, and he had earned an in-game nuke. 26

Those milestones are Heumann’s own updates, not independent verification that the reconstruction was complete. “Playable,” “nearly finished,” and “fully decompiled” describe different measures of progress; a game can run while parts of its code remain unfinished. His earlier account also described the project as a work in progress. 202628

What happened to the video and code link

After Heumann shared footage of the project, the video was disabled with a notice indicating that a copyright owner had reported it. Reporting also said the site hosting the code could no longer be reached. 2425

That distinction matters: the available reports document a disabled video and an inaccessible code-hosting link, but do not establish that Activision sent Heumann a cease-and-desist letter or that the entire project was formally taken down. 2425

How the case differs from Fallout: New York

The Fallout: New York project was a standalone browser game presented as a new entry in the Fallout universe, rather than an effort to reconstruct an existing game’s code. Its creator said ZeniMax sent a cease-and-desist notice, after which the project went offline. 34

The two cases therefore involve different projects and different reported responses: Heumann’s video was disabled after a copyright-owner report, while the Fallout: New York creator reported receiving a legal notice. Treating both as identical takedowns would overstate what the reporting establishes. 42425

What the cases do—and don’t—show

Both projects demonstrate how AI tools can help individuals build ambitious game-related projects quickly. They also show that public attention can bring a project to the attention of rights holders. But these reports do not settle the legal status of decompilation, fan games, or AI-assisted recreations in general. The practical lesson is narrower: using AI does not, by itself, prevent a publisher or platform from challenging a project, and the details of each project and response matter. 2024254