Mist-Locked Gate

Web browser (desktop and mobile)

By Hitesh K13 November 2026

Summary

Mist-Locked Gate (雾锁山门) is a free top-down 3D action game with a xianxia (Chinese fantasy) setting that runs in a web browser on computers and phones, with no install. You cross one misty mountain area, fight a group of regular enemies and then a boss with a second phase, using a three-hit combo, dodge, guard, parry, sword flight and an ultimate. The story text and the voice lines are in Chinese. Its developer, Guizang (歸藏, @op7418) on X, posted it on November 12, 2026, writing that the AI model Fable 5.2 made it for him in one afternoon.

Gameplay

The hero fighting a group of enemies in the snow Clip: Guizang (@op7418) on X

How it was made

Guizang described how it was made in a four-post thread on X and in the English README of his guizang-game-skill repository on GitHub, where he also released the workflow as an agent skill. The steps below follow those two sources; the clips and screenshots come from his launch video, his thread and the repository.

Step 1 Give the AI a theme and a plan
Guizang says his only creative brief was "Chinese fantasy" and that the AI made every creative decision from there. In the first stage of his workflow, the agent studies reference material, looks into how games like this are built and draws up a plan in stages before writing any code.
The hero on a snowy path beside a lantern and frosted grass Image: Guizang (@op7418) on X
Step 2 Turn concept art into 3D models
The agent made concept images with Jimeng, ByteDance's image generator, then turned them into rigged 3D models with Tripo, working through command-line tools and writing every prompt itself, he says. That produced 5 rigged characters, 2 weapons, 12 kinds of props and 5 kinds of loot. He found that models made straight from text looked poor, and concept image first worked far better.
Enemies waiting by a shrine gate in the snow, made from concept art with Tripo Image: Guizang (@op7418) on X
Step 3 Animate the fighters and tune the combat
Tripo offers only a few preset animations, so the agent computed the rest, placing hands and feet pose by pose. It then worked through a combat-feel checklist covering wind-up and recovery, hit-stop, knockback, guard and parry, and enemies that take turns instead of piling on. For effects it used meshes and shaders instead of large numbers of particles.
Sword-slash and shockwave effects around the hero Clip: Guizang (@op7418) on X
The three-hit combo sending projectiles across the snow Image: Guizang (@op7418), guizang-game-skill on GitHub
Step 4 Play-test and send feedback
Guizang stresses it wasn't made from one prompt: he play-tested the game 7 times and reported 5 to 10 problems each round, in plain words such as "the movement is stiff". The agent turned those notes into technical terms, looked them up and fixed them. It also checked its own work with frame-by-frame stepping, URL options that skip ahead to any stage, an F3 diagnostics panel and screenshots it took itself.
Step 5 Add sound and pack it into one file
The last stage added sound effects, 8 voiced lines, music and ambience, then compressed close to 100 MB of source assets into a single HTML file of about 33 MB. The same source also produces the hosted web version and an 8 MiB build for Xiaohongshu's offline mini-app container.

By Guizang's count, the build took about 6 hours and 450 million tokens, including some test runs on Opus 5.5, and a large share went on redoing work. His launch post said 4.5 billion tokens; in a follow-up post eight minutes later he corrected that to 450 million, blaming a voice-input typo. The skill itself is free under the AGPL-3.0 license and works with Claude Code, Codex and other agents, while the game's art, models, voice and music stay all rights reserved. Two hours after the launch post, he asked his followers whether the skill could repeat the result with a DeepSeek-based setup. All details here come from the developer's own posts and README: AIGamer hasn't verified the time or token figures and hasn't played the game to the end.

Sources

Details come from the developer's own posts and pages credited below.

Guizang (@op7418) on X: Launch post: Fable 5.2 made this 3D action game in an afternoon (in Chinese)
Guizang (@op7418) on X: Thread: assets made with Tripo and Jimeng CLI, 100+ MB squeezed to 30 MB (in Chinese)
Guizang (@op7418) on X: Thread: not one-shot, many rounds of revisions, and the skill (in Chinese)
Guizang (@op7418) on X: Correction: 450 million tokens, not 4.5 billion (in Chinese)
guizang-game-skill on GitHub: README (English)
guizang-game-skill on GitHub: README (Chinese)
Mist-Locked Gate: Play in the browser
Guizang (@op7418) on X: Post asking whether the skill can repeat it with DeepSeek (in Chinese)

Image: Guizang (@op7418) on X

Written in our own words; quotes are marked and credited. How we report

Summary

How it was made

Step 1 Give the AI a theme and a plan

Guizang says his only creative brief was "Chinese fantasy" and that the AI made every creative decision from there. In the first stage of his workflow, the agent studies reference material, looks into how games like this are built and draws up a plan in stages before writing any code.

The hero on a snowy path beside a lantern and frosted grass Image: Guizang (@op7418) on X

Step 2 Turn concept art into 3D models

The agent made concept images with Jimeng, ByteDance's image generator, then turned them into rigged 3D models with Tripo, working through command-line tools and writing every prompt itself, he says. That produced 5 rigged characters, 2 weapons, 12 kinds of props and 5 kinds of loot. He found that models made straight from text looked poor, and concept image first worked far better.

Enemies waiting by a shrine gate in the snow, made from concept art with Tripo Image: Guizang (@op7418) on X

Step 3 Animate the fighters and tune the combat

Tripo offers only a few preset animations, so the agent computed the rest, placing hands and feet pose by pose. It then worked through a combat-feel checklist covering wind-up and recovery, hit-stop, knockback, guard and parry, and enemies that take turns instead of piling on. For effects it used meshes and shaders instead of large numbers of particles.

Sword-slash and shockwave effects around the hero Clip: Guizang (@op7418) on X

The three-hit combo sending projectiles across the snow Image: Guizang (@op7418), guizang-game-skill on GitHub

Step 4 Play-test and send feedback

Guizang stresses it wasn't made from one prompt: he play-tested the game 7 times and reported 5 to 10 problems each round, in plain words such as "the movement is stiff". The agent turned those notes into technical terms, looked them up and fixed them. It also checked its own work with frame-by-frame stepping, URL options that skip ahead to any stage, an F3 diagnostics panel and screenshots it took itself.

Step 5 Add sound and pack it into one file

The last stage added sound effects, 8 voiced lines, music and ambience, then compressed close to 100 MB of source assets into a single HTML file of about 33 MB. The same source also produces the hosted web version and an 8 MiB build for Xiaohongshu's offline mini-app container.

Summary

Gameplay