Yuanzai World – LLM RPGs with branching world-lines
Hi HN, I'm Kai Wang, one of the creators of Yuanzai World. We built a simulation engine (currently on iOS & Android) that allows the community to create and share text adventures populated by multiple LLM-based agents. Unlike standard chatbots, our focus is on community co-creation—users define the worldviews, and our agents (with persistent memory and social relationships) bring them to life. The cool part: We implemented a system we call "World-Line Divergence" (inspired by visual novels like Steins;Gate). Usually, AI RPGs feel random or infinite loop. We built a state machine that tracks…
In plain words
Yuanzai World is a simulation engine for iOS and Android that lets users create and share text-based role-playing adventures featuring multiple AI agents with persistent memory and social relationships. Players define the world's rules while AI characters populate it, responding dynamically to player choices. The platform's "World-Line Divergence" system tracks how player interactions deviate from the original narrative, triggering branching story paths that lead to different endings rather than random or repetitive outcomes. It emphasizes community co-creation over standalone chatbot gameplay.
written from the facts on this page · September 2026
From the sources
In the maker’s words, at launch
Hi HN, I'm Kai Wang, one of the creators of Yuanzai World. We built a simulation engine (currently on iOS & Android) that allows the community to create and share text adventures populated by multiple LLM-based agents. Unlike standard chatbots, our focus is on community co-creation—users define the worldviews, and our agents (with persistent memory and social relationships) bring them to life. The cool part: We implemented a system we call "World-Line Divergence" (inspired by visual novels like Steins;Gate). Usually, AI RPGs feel random or infinite loop. We built a state machine that tracks "World Deviation." If players interact with NPCs in specific ways (e.g., convincing an artist to change their style), it triggers a graph switch, leading to a completely different generated ending, effectively breaking the original script. Tech Stack: - Backend: Python / Java with a custom AI orchestration framework (to handle agent concurrency). - Models: Hybrid routing between Gemini, GPT, and DeepSeek (optimizing for cost/performance based on task). - Vector DB: Milvus (for handling long-term agent memory). We are currently live on App Store and Google Play. Since it's a mobile-first experience, the link leads to our landing page where you can see the demo flow. Would love to hear your feedback on the "World-Line" concept: Does this state-machine approach solve the aimlessness of AI RPGs?
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