Meta's new Horizon Creator Competition puts AI-assisted browser game development on a tight leash: three weeks, one portrait-mode core loop, a self-contained Three.js/HTML5 build, and no network requests at runtime.
Official Meta Horizon Creator Competition
ARTICLE
Meta has opened registration for the Horizon Creator Competition: Game Prototype, a three-week challenge asking existing Meta Horizon Creator Program members to turn prompts into genuinely playable mobile game prototypes. Submissions open August 17 at 10:00 AM Pacific and close September 8 at 1:00 PM Pacific. The required delivery format is unusually concrete: a self-contained Three.js/HTML5 web build.
That last detail makes this more than another broad AI hackathon. Browser game technology is the submission target, not an optional track. Entrants choose survival and resource management, simulation and management, or tower defense and strategy, then build one single-player core loop for portrait orientation.
A browser build that has to stand on its own
The package rules are strict enough to be interesting. Each game must arrive as a ZIP no larger than 35 MB, with index.html at the top level. The entrant's readable, unminified game code must be assembled into that file. Third-party libraries such as Three.js belong in a local vendor folder, while every asset, font, sound, and data file must ship inside the package.
Prompt-built, with receipts
Meta is explicitly testing AI-led production. Entrants can use any AI tool, but prompting is supposed to do the heavy lifting. Minor hand-written fixes and tuning are allowed. A required Markdown build log records the decisions and each working session so judges can see how the prototype was made. A separate, anonymous design-intent document provides context but is not scored.
Playability before polish
The judging weights reinforce that point: player engagement accounts for 30 percent, playability 25 percent, core-loop design 20 percent, focus 15 percent, and originality 10 percent. Visual polish is explicitly excluded from scoring.
Meta lists $300,000 across 12 awards. There is an important qualifier: half of every listed award is a completion grant tied to rebuilding the prototype with Meta's Early Access creation tools and completing a separate checklist. The grant is not guaranteed.
This is also not an open call for every Three.js developer. Entrants must have been active Meta Horizon Creator Program members, meet the geographic and age requirements, and remain in good standing. For more up-to-date information, be sure to refer to their information page.
What is already clear is that Meta has chosen the browser stack as the proving ground for a prompt-built game pipeline. The resulting project gallery may be the more interesting part of the story.
Source: Meta Horizon Creator Competition: Game Prototype, sponsored by Meta and managed through Devpost. See the official rules for eligibility, timing, submission, prize, and completion-grant terms.