Battle Drones - a vibe coded RTS with audio-based multiplayer

Blog · Watch/Read · (gathered 2026-10-21)

• Simon Willison developed “Battle Drones,” a complex and genuinely fun RTS game, primarily through “vibe coding” with LLMs (Claude Code), demonstrating that coding agents can create sophisticated and enjoyable games even in domains where the human developer has minimal expertise.
• A pivotal moment was the prompt “Make it a LOT more fun” given to Claude Opus 5.5 in Ultracode mode, which led to significant gameplay improvements, new features, and rebalancing through thousands of simulated playtest sessions, showcasing the LLM’s capacity for self-directed design and optimization.
• The game features innovative multiplayer via audio signals (later supplemented by low-cost online WebSockets due to user feedback), “Agent battles” where LLMs play against each other, and a fully code-generated 3D environment and adaptive music, all built by the AI.
• The project highlights the power of static HTML/JavaScript/WebGL/Three.js as a game development medium for LLMs and raises questions about the “guilt” of creating high-quality software with minimal personal coding effort, suggesting a path for “vibe coded games” to be taken seriously.