One Chinese prompt, one 3D block game in Claude Code: the full prompt and a demo mode

This 3D block game was written by Claude Code from one Chinese prompt: a single HTML file you open in a browser, with two roles, a wall archer and a rock golem. This guide gives you the full prompt, the install and login steps, how to play both roles, and my favourite trick: ask for a "demo mode" so the computer plays itself and you just record. The images are real footage of our game running, plus frames from the Reel.

01What you will build: a playable 3D block game

3D block game: a rock golem smashes into the stone wall and grey block fragments fly, score and wave top-left — Real footage of the game itself: the golem smashes the wall and block fragments fly.

The game in the Reel was written by Claude Code from one Chinese prompt: a single HTML file you open in a browser. It has two playable roles, a score, waves, a wall health bar and block-burst effects. The screens below were recorded from the game running for real, not drawn.

The game's start menu: the title, two buttons for the wall archer and the rock golem, and a controls box — The start menu: title, two role buttons and controls, all asked for in the prompt.

Many people think making a game takes a whole team: design, art, code. A small game doesn't. You describe the look, the theme and the roles clearly, and Claude Code does the rest.

Reel frame: a wall note asks if making a game takes a whole team, small block characters at desks, orange mascot — From the Reel: "Does making a game take a whole team?" (The studio is a made-up scene, not a real company.)

Here is the order: first check that your plan includes Claude Code, then paste the prompt, then how to play the two roles, and finally my favourite trick: ask for a "demo mode" so the computer plays itself and you just record.

02Step 1: make sure you have Claude Code

Claude Code is not part of the Free plan. I checked Claude's official pricing page on 20 October 2026: the Claude Code row says "No" for Free and "Yes" for Pro and Max. Pro is $17 a month on an annual plan ($200 billed up front), or $20 if billed monthly. The page also notes that usage limits apply and that prices and plans may change, so check the site.

Claude's pricing page: Free, Pro and Max cards, with a "Claude Code included" tag on Pro and Max — The official pricing page (screenshot taken 2026-10-20): Pro and Max carry a "Claude Code included" tag.

Claude Code's site says it is available for macOS, Linux and Windows, and works in the terminal, VS Code, JetBrains, the desktop app or the web. You can download the desktop app from the site or install it in a terminal.

Claude Code product page: big heading, a download button, and the other ways to use it — The official product page: claude.com/product/claude-code

The official docs (code.claude.com/docs/en/overview) list these terminal install commands. Pick your system:

macOS, Linux or WSL: open a terminal and paste curl -fsSL https://claude.ai/install.sh | bash
Windows PowerShell: paste irm https://claude.ai/install.ps1 | iex
When it finishes, open a new terminal window and type claude --version. If it prints a version number, you're set.
The first time you run it, Claude Code asks you to log in. Use the Claude account that has Pro or Max.

03Step 2: paste this prompt

This is the full prompt I used in the video. Swap the ［］ parts for your own theme and roles. Please invent your own theme and don't use characters from someone else's game, film or anime.

Game prompt (replace the ［］ parts with your own theme and roles)

Build me a complete 3D block-style browser game in the look of Minecraft, all inside one index.html in this folder (load three.js through an import map from https://unpkg.com/[email protected]/build/three.module.js, write everything else yourself, no external assets, textures drawn in code as pixel textures).

Theme: "［Block Island Defence］". ［A small block island with a village and a stone wall in the middle; giant rock golems walk out of the forest towards the wall, wave after wave.］

The player picks one of two roles at the start:
1. ［Wall archer］: stands on the wall, aims with the mouse, clicks to fire flaming arrows; a hit bursts the golem into block fragments, and a combo text pops up for consecutive kills.
2. ［Rock golem］: third person, WASD to move, space bar to charge; when you hit the wall its blocks fly off.

Include: a start menu (game title, two role buttons, controls), score, wave number, wall health bar, a message when a golem is defeated, block-burst particles, sky and clouds, trees, water, daylight shadows.

Also add a demo mode: when the URL ends in ?demo=archer or ?demo=golem, skip the menu and let the computer play that role (auto-aim and shoot / auto-walk into the wall), with a good-looking camera, so it is easy to screen-record.

When you are done, check there are no syntax errors, and finish by telling me in three short lines how to start playing.

Reel frame: Claude Code on a laptop, a sheet with the Chinese prompt landing on it, orange mascot in glasses nearby — This step in the Reel: one Chinese prompt, and not a line of code written by hand.

Create a new empty folder on your computer. Any name will do, for example block-game.
In a terminal, go into that folder (cd block-game) and type claude to open Claude Code.
Paste the whole prompt above, send it, and wait while it writes.
When it's done it will tell you in three short lines how to play. In practice that means finding index.html in the folder and opening it in Chrome.
Pick a role and play.

The file we got is about 387 lines, all in one index.html. The game loads three.js from the internet, so you need to be online when you open it.

Code editor view of index.html showing the code that builds the rock golem, header says 387 lines — The index.html we got this time: 387 lines, one file.

04How to play the two roles

The start menu lets you pick one of two roles. In our version the controls are:

Wall archer: aim with the mouse and click to fire a flaming arrow. A hit bursts the golem into block fragments, and consecutive kills pop up a "combo".
Rock golem: W and S to go forward and back, A and D to turn, space bar to charge. When you hit the wall, its blocks get knocked off.

Archer mode: a "Combo ×3!" message and a wave banner while a golem bursts into grey fragments on the grass — Archer mode: knocking down golems pops up a combo.

Golem mode: the rock golem surrounded by flying grey block fragments, score 3140 in the top-left corner — Golem mode: you are the one smashing the wall.

05The best trick: ask for a demo mode

My favourite trick is the demo mode. Add ?demo=archer or ?demo=golem to the end of the URL and the computer plays that role by itself, so you don't have to touch anything and can just record your screen. That's how the game footage in the Reel was captured.

Reel frame: a browser window with index.html?demo=archer in the address bar, the game menu inside, an orange tag — Add ?demo=archer to the end of the address bar and the computer plays the archer by itself.

The prompt above already asks for it. If your game is already built and you didn't ask for it, add it afterwards with this:

Prompt to add demo mode later

I already have index.html. Please add a demo mode: when the URL ends in ?demo=archer or ?demo=golem, skip the start menu and let the computer play that role (auto-aim and shoot / auto-walk into the wall), with a good-looking camera so I can screen-record it. Don't change anything else.

Find index.html in the folder, then edit the address in the browser so it ends in index.html?demo=archer and press Enter.
To watch the golem instead, change it to ?demo=golem.
Record it with your computer's or phone's built-in screen recorder.

06When it isn't perfect, how to fix it

The first version is rarely perfect. We went through a few rounds too: the debris was invisible at first, the auto-playing character walked through the wall, and the camera angle looked bad. We played it, told Claude Code what we saw, and asked it to fix them. So "not one line of code" in the Reel means I wrote none by hand; the fixes were made by Claude Code as well.

Fix-it prompt (replace the ［］ parts with what you see)

I opened index.html and played it. A few things need fixing:
1. ［e.g. the debris is sometimes invisible］
2. ［e.g. the auto-playing character walks through the wall］
3. ［e.g. the camera is too close to see the whole wall］
Please fix them one at a time, tell me what you changed, and leave everything else alone.

07Things to watch out for

Plan: Claude Code needs Pro or higher; the Free plan doesn't include it. Prices and limits are on the official site, and I checked on 20 October 2026.
We ran this prompt for real with Claude Code, and the game footage in the video is a genuine recording of our game running. But every run is different, so yours won't match mine.
"Like Minecraft" only describes the block style. Our game, Block Island Defence, is our own theme and has nothing to do with Minecraft or any other game. When you make yours, invent your own theme and don't borrow someone else's characters.
The game needs an internet connection to load three.js. Offline, the screen won't open.
Build it in a new empty folder, not one that holds important files. Claude Code creates and edits files in the folder.
Usage limits apply. If you keep iterating and fixing, keep an eye on your plan's usage.