Alibaba's ATH Innovation Division released HappyOyster on April 16, an open-ended world model that generates persistent 3D environments with real-time audio-video synthesis and interactive physics. Built on a natively multimodal architecture, HappyOyster supports two modes — Directing (user-guided video stream) and Wandering (first-person procedural exploration) — and targets game development and film production. The model comes from the same ATH team behind HappyHorse and is currently in limited early access.