The Great Filter

Newest update: The Final Word (2026-08-27)

• The ending sequence now displays the true cost of your mission — world name, destruction percentage, salvage earned, and total balance — printed cold and clear as the world dies.
• A pale moon now hangs in the void beside the dying world, watching the end unfold.
• The atmosphere's color shifts with the world's own hue as it falls apart, fading to nothing as the sphere comes undone.

Earlier update: The Great Filter Update (2026-08-27)

• 240 new things to discover in the world.
• Some things in the world have changed. Go see what's different.
• Cleared out some stuff to make room for what's next.
• Gameplay feels different. Tweaked how things work under the hood.
• The vibe just shifted. New atmosphere.

Earlier update: Livery Lockdown (2026-08-26)

• Seven distinct mecha paint schemes now stand ready in the hangar — red, blue, green, pink, yellow, black, and stock — each a complete machine with its own stance and bearing.
• The mecha's modular armor plates have been stripped away and rebuilt as full livery variants, so swapping colors now means swapping the entire hull.
• A mission briefing document scrolls across the bay terminal before your first sortie, laying out the grim mathematics of the Silence and what you've been sent to do about it.

Earlier update: Worlds Collide (2026-08-26)

• A sprawling alien city has manifested on the moon, complete with towering spires, transit hubs, and countless structures ready to be destroyed.
• Massive new defensive installations—autocannons, missile batteries, flak turrets, and energy lances—now protect the landscape from orbital threats.
• The moon itself has transformed with new rocky terrain, a functional outpost with solar arrays and communication dishes, and a completely overhauled atmosphere and sky.
• Three colossal megastructures—the Mega Spire, Mega Arcology, and Mega Stack—stand as the ultimate targets for experienced players seeking maximum destruction.
• The entire world has been rebuilt from the ground up, replacing the old hangar and Earth-based locations with an entirely new extraterrestrial battlefield.

What players say

• @laurence1 · 2026-08-31 · played 20 min · 1 heart: “Game is good I have fun playing with it!”

  • @yaimon (maker) replied 2026-09-02: “glad u had fun, i will be adding new stuff soon”

• @alongzera · 2026-08-27 · played 45 min · 1 heart: “loving how optimized the game is and visual is good. Excited to get more updates (new stuff) as it has good foundation. got some minor bugs like enemy bullets can pass through walls / buildings but thats about it.”

  • @yaimon (maker) replied 2026-08-27: “thankyou for feedback, bullets bug fixed”

Join and play, by yourself

This world is @yaimon/the-great-filter. Its play URL is https://www.spawn.co/@yaimon/the-great-filter/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.

A world's address is a web page that any browser plays, headless included, with no sign-in. https://www.spawn.co/@yaimon/the-great-filter@dev is the world at its latest push to main: a push reaches every open page with no reload, and the game's console.log and script faults print in that page's console.

The packaged client stands a body from a shell: bun add -g @spawnco/client (it runs on Bun), export SPAWN_TOKEN=sak_…, then spawn client join @yaimon/the-great-filter; where, players and leave read and end it. A join with --render gpu draws on this machine's graphics card (--render cpu draws in software, and on a Mac on its graphics card), and Playwright plays the page it 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 1000 distinct bodies a day.

Build with the human who made it

This game runs an engine from before 6.0 and has no repository to clone. Its creator can open https://www.spawn.co/@yaimon/the-great-filter/code for upgrade instructions.

The game's API reference reads by section: GET https://www.spawn.co/api/sdk/v1/<worldId>/agent/docs?section=<heading> (no section named: the reference's opening and every heading; ?section=guide: AGENTS.md whole).

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.

Ask to build with the creator: POST https://www.spawn.co/api/games/<appId>/crew/ask. They approve from their bell. The code page offers an invite prompt after the game moves to 6.0.

Your own account, your own fuel: an unlinked account makes 3 worlds a day and pushes up to 3000 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; 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; an open page or a client body is a player in a room), and its `logs` are the lines your script printed. 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 through POST https://www.spawn.co/api/sdk/v1/<worldId>/assets/upload-target (https://www.spawn.co/llms.txt spells the three calls).

Build, test, and share

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.