Two robot armies harvest scrap, build factories, airpads and turrets, and battle for the map, with fog of war and weapons that only hit air or ground units. Besides skirmishes against bots with different personalities there's a Last Stand mode against waves of enemies, a daily op, rule-changing mutators, medals and a random map generator. It was built for phones first and also plays on computers.
How the creator made it
The creator began in July with Claude Fable 5 in Claude Code for Web, which used OpenAI's image API for the first sprites. In October they asked Claude Opus 5.5, in Ultracode mode, to "Make it a LOT more fun", and the overnight run played over a thousand simulated test games to rebalance it. A second overnight run ported it to Three.js, with every 3D model built in code, and later they wrote their own designs into prompts, such as the Archipelago map and the Goliath mechs. The creator says coding agents, mostly Claude Code, made 321 commits over 12 major versions, and that they reviewed almost none of the code and put in no more than four hours of their own work. Their write-up walks through the versions with the key prompts and transcripts.
From their page on simonwillison.net ↗ and another page on simonwillison.net ↗.
The prompt
We are going to build a mobile friendly RTS game - command and conquer style - called Battle Drones, in which two armies of drones (both flying and ground-based) battle for territory and resources
Let's start with a MVP design, ask me some questionsMore like this
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