This paper presents a comprehensive framework for automating the process of creating card game prototypes using large-scale language models (LLMs). Key features include a graph-based indexing method for generating novel game mechanics beyond existing databases, an LLM-based system for generating consistent game code validated by gameplay records, and a method for building a gameplay AI that utilizes an ensemble of LLM-generating heuristic functions optimized through self-learning. This approach aims to accelerate card game prototype development, reduce human resources, and lower the barrier to entry for game developers.