---
title: "The Cradle: Episode 01"
url: "https://aigamehub.app/ja/games/i-built-a-custom-horror-game-engine-with-claude-code-in-4-we-15a00b"
source: "https://www.reddit.com/r/ClaudeCode/comments/1x3pqx7/i_built_a_custom_horror_game_engine_with_claude"
source_type: "reddit"
play_url: "https://0xkot.itch.io/the-cradle-episode-01"
platform: "both"
login_required: false
pricing: "free"
origin: "original"
ai_tools: ["Claude Code"]
game_languages: []
author: "EconomyPrudent6511"
author_handle: "EconomyPrudent6511"
category: "アクション"
categories: ["action", "adventure"]
tags: ["browser", "first-person", "horror", "itch.io", "solo-dev", "three.js"]
added: "2026-10-16T17:11:53.799Z"
updated: "2026-10-16T17:11:53.799Z"
locale: "ja"
content_locale: "ja"
---

# The Cradle: Episode 01

ソロ開発者による無料のブラウザベースのナラティブホラーゲーム：廊下や部屋を探索し、鍵を見つけ、ノートを読み、あなたを追いかけるクリーチャーから隠れ、脚本された脅かし、停電、エレベーターを生き延びる。three.js によりブラウザで動作し、携帯電話でも遊べる。

## Description

『The Cradle: Episode 01』は、開発者自身の Narrative Horror Runtime エンジンで構築され、three.js でレンダリングされた一人称ナラティブホラーゲームです。そのため、インストール不要でブラウザ（および携帯電話）で直接プレイできます。Windows と Steam Deck のビルドも存在します。プレイ内容は、廊下や部屋を移動し、鍵を見つけて施錠されたドアを開け、ノートを読み、隠れ場所を使い、プレイヤーを追いかけるクリーチャーを避けることです。脚本された脅かし、停電、動作するエレベーターもあります。作者はこのゲームが無料であること、そしてコードの大部分が Claude Code で書かれたと述べています。同じ投稿から、より短いハロウィンのサイドゲーム『The Cradle: Trick-or-Treat』もリンクされており、ブラウザでプレイできます。

## Original post

I built a custom horror game engine with Claude Code in 4 weeks. 200+ people have played the games and 7 streamers have streamed them

Four weeks ago I had an empty folder. Today there's a custom horror game engine, two games live on itch.io , 200+ players, and 7 streamers who've played it on stream. I'm a solo dev, and most of the code was written by Claude Code. Here's how it actually went. What I built NHR (Narrative Horror Runtime): an engine made for one genre only, narrative horror. Corridors and rooms, locked doors and keys, notes, hiding places, a creature that hunts you, scripted scares, power cuts, lifts. It runs in the browser on three.js, phones included, and ships as Windows and Steam Deck apps too. On top of it, the tooling: a map compiler: write a level as YAML, get a 3D map a 2D room planner: draw rooms in metres, round halls, stairs, working elevators a 3D editor: one-click "dress this room", props, lights, story triggers, doors and keys real ray-traced light baking on a GPU box (Blender Cycles, driven remotely) an original score and sound effects, all generated in code The numbers Started 15 September. 866 commits and 227 merged PRs since. Episode 01 went from first file to playable on itch in under two weeks. The Halloween side game, Trick-or-Treat, took 3 days from first file to live. 7,000+ automated tests, including a full QA of every level: every key can be reached before its door, every room can be walked to, nothing flickers. 200+ players, 7 streamers, and so far the feedback has been really positive. How I worked with Claude Code Plan first, then build. I describe what I want, Claude proposes a plan, and I approve or change it before anything is written. Parallel agents in git worktrees. Often 2–3 at once: one on the level editor, one on a bug, one on a release. Each opens a PR, and I review screenshots and merge. Everything is text. Levels, stories and placements are YAML, JSON and Python, so every AI change is a diff I can read and reject. A LESSONS.md file. Every bug class we ever shipped, plus the rule that now prevents it. Claude reads it before planning, and the same mistake rarely happens twice. The tests are the safety net. Agents prove a fix with headless playthroughs, pixel diffs and before/after screenshots, not just "should work". Things I learned the hard way Tell it about your environment. My Mac must never run Blender with GPU rendering (it crashes), so all Blender work runs on a separate Linux GPU box. And games play sound, so every in-game test runs headless and muted, or I'd hear horror screams at 2 am. Guard your hardware. I run a local LLM on the same GPU, and a bake once silently fell back to the CPU after a driver update broke. Now every bake script checks the GPU and free VRAM first. Small stacked PRs beat one giant one. The editor UI refactor went in as 5 stacked PRs, each tested on its own. Here's a 60-second video of a whole level going from a blank page to playable with these tools: https://www.youtube.com/watch?v=uoYc_QS2bSo Play the games (free, in your browser, no install): 🎮 The Cradle: Episode 01: https://0xkot.itch.io/the-cradle-episode-01 🎃 The Cradle: Trick-or-Treat: https://0xkot.itch.io/the-cradle-trick-or-treat Happy to answer anything about the workflow, the engine or the prompting. And if you play it, I'd love to hear what scared you. 👻   submitted by   /u/EconomyPrudent6511   to   r/ClaudeCode [link]   [comments]