BlockHaven: WebGL2 Minecraft-style survival
A sandbox game kepo built with Claude Opus 5.5. Copy the exact prompt free.
@kepochnik built this with Claude Opus 5.5 and shared the full prompt on X; it is quoted below word for word. I built Minecraft thanks to Opus 5.5 for me, this is literally the best AI model that can be right now this game name - BlockHaven it took me a little over an hour and a half to complete this game, and here's the result should I publish this game for everyone? The original post had 4.2K views.
The prompt
Build a browser sandbox game in the spirit of Minecraft that feels as close to the original as possible. All in-game text in English. Controls: keyboard and mouse (desktop). TECH - A single HTML file, plain WebGL2, no third-party libraries. - All 16×16 textures generated in code as pixel art (stone, dirt, grass, planks, leaves, ores, glass, water, lava, etc.). - Sounds synthesized with WebAudio: digging, footsteps, placing blocks, damage, mobs, explosions, calm background music. WORLD - Infinite world made of 16×16×128 chunks, with a seed. - Biomes: plains, forest, birch forest, taiga, snowy tundra, desert, mountains, oceans, beaches. - Caves (winding tunnels and large caverns), lava at the lower levels, ores by depth: coal, iron, gold, diamonds. - Three tree types, tall grass, flowers, cacti, sugar cane, pumpkins. - Minecraft-style lighting: sky light and block light (torches, glowstone, lava) that spreads cell by cell, with smooth lighting and ambient occlusion. - Day/night cycle: sun, moon, stars, sunsets, 3D clouds, distance fog, rain. - Water and lava flow by levels; two sources make infinite water; water + lava make obsidian or cobblestone. Sand and gravel fall. PLAYER - First person, collisions, jumping, sprinting, sneaking (doesn't fall off edges), swimming, ladders, fall damage. - Block breaking with crack stages and particles; break time depends on the tool. - Visible hand and held item with a swing animation. Third-person view on F5. SURVIVAL - Health, hunger, saturation, air underwater. - Tools in 5 materials with durability, armor in 4 materials. - Inventory with 2×2 crafting, 3×3 crafting table, furnace with fuel, chests, bed (skip the night and set spawn). - Item drops, death and respawn. - Mobs: pigs, cows, sheep, chickens (breeding, shearing); at night zombies, skeletons with bows, spiders. Zombies and skeletons burn in sunlight. - Farming: hoe, seeds, wheat growth, bread. Doors, fences, fence gates, TNT. CREATIVE - Flying on double-tap Space, instant block breaking, a catalog of all blocks with tabs and search. UI - Title screen with a world panorama, world list (create / delete / play), options (FOV, render distance, sensitivity, sound, brightness, GUI scale). - Pause menu, death screen, HUD (hotbar, hearts, hunger, armor, air bubbles), F3 debug screen. - Chat with commands: /gamemode, /time, /give, /tp, /summon, /weather. - Worlds saved in localStorage. RESTRICTIONS - Do not use Minecraft's name, logo, textures or characters (Steve, Creeper, etc.): give the game its own name and design your own mobs. TESTING - Run the game in a headless browser, check every system and fix bugs before delivering.
Prompt by kepo (@kepochnik), quoted word for word from the original post. Model as stated by the creator; your result will differ.
What’s inside
- Copy the prompt below, or download it as a SKILL.md
- Paste it into Claude Opus 5.5, ideally in Claude Code so it can write, run and test the game
- Swap in your own theme, characters or rules where the prompt names theirs
- Play it, then ask for fixes and polish in plain words
What you’ll bring
- Claude Opus 5.5 (Claude Code, or a Claude chat for single-file HTML games)
- A browser to play the result
- Your own twist on the idea, if you want one
What you’ll get
- A playable browser game in the spirit of the one above, written by Claude
- The code, which you can keep editing
Perfect for
- Anyone who wants to make a game without coding
- Developers testing what Opus 5.5 can build
- Teachers and parents making a game with kids
Also found as
opus 5.5 game prompt · claude game prompt · one shot game prompt · sandbox · blockhaven: webgl2 minecraft-style survival
Questions
What is BlockHaven: WebGL2 Minecraft-style survival?
BlockHaven: WebGL2 Minecraft-style survival is a sandbox game that kepo (@kepochnik) built with Claude Opus 5.5. This page quotes the prompt they shared, word for word.
Who made it, and where was the prompt shared?
kepo (@kepochnik) made it and shared the prompt on X: https://x.com/kepochnik/status/2103502454750920925. You can find more from them at https://x.com/kepochnik.
How do I use the prompt?
1. Copy the prompt below, or download it as a SKILL.md. 2. Paste it into Claude Opus 5.5, ideally in Claude Code so it can write, run and test the game. 3. Swap in your own theme, characters or rules where the prompt names theirs. 4. Play it, then ask for fixes and polish in plain words.
Is it free?
Yes. Copying the prompt and downloading the SKILL.md costs nothing on Omo. You run it with your own access to Claude Opus 5.5.
The video and the prompt belong to kepo. Omo lists them free, with credit and a link to the original post. Creators can ask us to remove a listing at omo.space/support.