Unreal Engine 5.8 became the latest setback for Ziwen Xu’s 12-day attempt to build an AI-generated GTA 6-style game, with Xu saying the new MCP tools slowed the development loop instead of speeding it up.
The slowdown hit after rapid early progress: by day 3, AI agents had added NPCs, traffic, shadows and reflections, but they also began recreating Los Angeles rather than Miami-inspired Vice City.
Day 7 brought a switch from Godot to Unreal Engine 5, and day 8 brought a hardware failure when Xu’s Mac crashed after multiple agents opened the game simultaneously to take screenshots.
The project still produced an in-game phone with maps, contacts and a wallet, but the experiment underscored how far AI remains from autonomously building a Rockstar-scale open-world game ahead of GTA 6 preorders next week and its Nov. 19 release.