Claude Opus 5.5 Powers a Browser-Playable Pokemon-Style Battle Demo as Agentic Game Tests Spread

A browser-playable, unofficial Pokemon-style gym battle demo built with Claude Opus 5.5 has become an early example of how the new model is being used for end-to-end game prototyping. The project was described as a high-effort build completed in a couple of hours, with an image model generating the background while Opus 5.5 handled most of the remaining work, including gameplay code, sound effects and music.