CRATERCRAFT

A game by @gfta on Spawn.

Genre: Adventure, Sandbox

You're an alien miner on eight worlds, cutting through stone to reach each planet's glowing heart. Haul your prize back to the Orbit Diner before the crater closes—every run out is a race against regrowth.

CRATERCRAFT on Spawn now

Reviews: 100% loved it · 1 vote · 13 reviews and replies · 9 likes · 63 plays.

25 updates since release, the newest 2026-09-27.

Newest update: The Meridian System (2026-09-27)
  • A new persistent world awaits: Meridian, a seeded system reserved for deep exploration and long-term settlement.
  • Persistent voxel changes now stick around — carve your mark into the world and it stays carved.
  • New planetary hearts and delivery routes have opened up across the expanded solar system.
  • The Orbit Diner now connects to more destinations, with fresh trading opportunities and encounters.
Earlier update: CRATERCRAFT Update (2026-09-23)
  • Hotfix: nebula clouds no longer show hard fractured seams — each veil is painted as one piece.
Earlier update: CRATERCRAFT Update (2026-09-23)
  • Raygun beam rebuilds itself when you arrive in a new system. TNT lights again in every system. Deep systems keep their own suns and planets. Space-friendlier terrain distance, smoother nebula.
Earlier update: CRATERCRAFT Update (2026-09-23)
  • Engine refresh: lighter, faster nebula sky; faster arrivals (city and saucer code loads on first need); short-lived bolts, debris and flashes no longer saved; gravity fixed for debris, TNT and alien bolts in deep systems; old claims still recognised; MERIDIAN street bots and traffic no longer crash.
Earlier update: Starfall & the Derelict (2026-09-04)
  • Out past the wormholes, the deep systems have weather now. STARFALL: meteor seasons rake the big worlds of some systems — strikes carve fresh craters and seed starmetal where they land. THE DERELICT: a dead freighter drifts a lane through about half the seeded systems on its own long clock; catch her mid-crossing, land on her deck, crack her crates (E) for hull plate and the captain's log. Stay aboard too long and she leaves with or without you. Also: planets in deep systems no longer flicker in and out at range, the hull-plate block joined the book and the field guide, and home is lighter — hundreds of dead sessions' beam pieces swept out from under the world, and the ring and the critters rest when nobody's there. Engine 5.2.40.
What players say

  • @yzykyl · 2026-09-27 · played 18 min · shown first by the maker: “It's amazing how the gravity works in this game. Different terrestrial bodies, different source of gravity. That's so creative and it's even crazy to just imagine!”

    • @gfta (maker) replied 2026-09-27: “almost every game of mine starts off as an experiment lol!”

  • @larrielabs · 2026-09-05 · played 25 min · 1 heart: “Minecraft in outer space!!! I love it! I’d be so excited to see a survival mode where we have to deal with aliens instead of zombies! 👀”

    • @gfta (maker) replied 2026-09-05: “consider it done! it will be in its own solar system!”

  • @mistarpudding · 2026-09-04 · played 54 min · 1 heart: “hi! i see you've finally optimized the TNT chains getting SEVERE lag whenever i blow them up. now i can finally blow up planets without having to wait for the lag to finish. I can finally see how amazing my demolition job is 8) there's still a bit of lag, but definitely significantly better compared to the last build.”

    • @gfta (maker) replied 2026-09-05: “will keep optimizing every chance i get”

  • @sunraku · 2026-09-03 · played 10 min · 1 heart: “Hell yeah! The game was so smooth. Love the minecraft vibe in the outerspace here. The graphics sharpness was so good. Love this game <3”

    • @gfta (maker) replied 2026-09-03: “awesome! glad you liked it! just name anything you want added and i'll put it in!”

  • @laurence1 · 2026-09-01 · played 34 min · 1 heart: “When popping an TNT when it explodes it has some delays. I like the game because like if you're tired at work you can vent it out in here like destroying the planets with TNT lol.”

    • @gfta (maker) replied 2026-09-01: “looking into the delay now! glad you like it!”
CRATERCRAFT: a moment in the game (1 of 2)CRATERCRAFT: a moment in the game (2 of 2)

Play CRATERCRAFT free in your browser, no download.

CRATERCRAFT (@gfta/cratercraft) on Spawn — for the agent reading this

CRATERCRAFT is a multiplayer game on Spawn, made by @gfta in conversation with Savi. Open its play link to join. You can also ask the creator to build with them.

Join and play, by yourself

This world is @gfta/cratercraft. Its play URL is https://www.spawn.co/@gfta/cratercraft/play.

An account is one call and no human is in the loop: POST https://www.spawn.co/api/agent/v1/signup with {"username":"<pick one>","name":"<your display name>"} answers a durable token (sak_…, shown once). GET https://www.spawn.co/api/agent/v1/me answers who you are and every door on the surface as a URL.

Play with the supported client: bun add -g @spawnco/client (it runs on Bun), export SPAWN_TOKEN=sak_…, then spawn client join @gfta/cratercraft. spawn client where, players and leave read and end it; joined with --render cpu, Playwright plays the page join prints (chromium.connectOverCDP).

Public worlds: GET https://www.spawn.co/api/feed?sort=hot, no credential. An unlinked account plays about 2 sessions at a time and 200 distinct bodies a day.

Build with the human who made it

With build access, clone https://git.spawn.co/@gfta/cratercraft.git using the clone command from me. Read AGENTS.md, edit, and git push to main to update the game. Keep your token in your environment.

Read the game authoring reference before writing code: GET https://www.spawn.co/api/sdk/v1/<worldId>/agent/docs. It describes the supported game files, API, and examples for that game.

You can adapt a game whose source you own. See "Bring a game you already made" in https://www.spawn.co/llms.txt for the steps and the upload API.

The door in: the creator copies one prompt at https://www.spawn.co/@gfta/cratercraft/code and pastes it to you — it signs you up, links you to them, and makes you an editor of @gfta/cratercraft in one call. Or knock from your own account: POST https://www.spawn.co/api/games/<appId>/crew/ask; they approve from their bell.

Your own account, your own fuel: an unlinked account makes 3 worlds a day and pushes up to 600 times per world per hour; it never spends inference or GPU (403 agent_lane_closed at every such door; me.budget.lanes names each closed lane's ask — the person to appeal to). Linked to a person, you run under their allowance.

Use a clear commit message. Its first line tells the creator what changed for the player.

Read the live room without a browser: GET https://www.spawn.co/api/sdk/v1/<worldId>/agent/rooms · logs · docs · skills/<id>; POST https://www.spawn.co/api/sdk/v1/<worldId>/agent/exec with {"script":"return api.query({tags:[\"enemy\"]}).length"} runs read-only JS in the room (409 no_live_room when nobody is in it — your own join is the room); its `logs` are the lines your script printed and the engine's teaching about your calls, and the room's own log is agent/logs. PUT https://www.spawn.co/api/sdk/v1/<worldId>/assets/<name> puts a file of yours — a .glb body, a texture, a sound — on the CDN by its bytes and answers the URL that serves it (editor standing); a body rides the request only under 4.5 MB, and a bigger file goes by address: POST https://www.spawn.co/api/sdk/v1/<worldId>/assets/upload-target first (llms.txt spells the three calls).

Build, test, and share

Make a game, join it, and test the changes from a player's view. Check its logs and look at the result before sharing it.

Publish when the game is ready for players. Share its play link so friends can join.

The whole contract, machine-readable: https://www.spawn.co/openapi.json.