The growing use of escape games in education has led to innovative digital tools that support learning and teaching. This paper introduces the Escape Game Chatbot, a ChatGPT-based tool that assists users in co-designing educational escape games through guided narrative planning, puzzle creation, and alignment with learning objectives focused on Sustainable Development Goals. The Escape Game Chatbot aims to lower design barriers for educators and game designers lacking expertise in this context. A formative evaluation with 15 university participants indicates positive impacts on design understanding, creativity support, and the likelihood of the Escape Game Chatbot’s reuse.