The impacts of climate change are becoming increasingly significant, and children have some misconceptions about climate change knowledge. It is necessary to provide children with accurate knowledge about climate change so that they can develop a sense of responsibility for climate action from an early age. Currently, climate change education is typically delivered directly in the classroom, which makes it difficult for children to develop an interest in climate change knowledge. One of the challenges in climate change education is how to spark children's interest in the topic. By prototyping counterfactual scenarios that deviate from conventional user-centered principles, the role of the user changes to the imaginer. In China, climate change is closely related to the 24 solar terms. The 24 solar terms are widely regarded as an ancient Chinese system for dividing time based on the annual movement of the sun. Existing studies have suggested that climate change has affected the climatic characteristics of the 24 solar terms. Based on the correlation between the 24 solar terms and climate change, this study designed a climate change serious game titled “Climate Hero”, themed around the 24 solar terms. It combines mechanisms of airplane chess and puzzle games. In the game, children can play as heroic animal characters and restore the puzzle, symbolizing the return of climate balance. “Climate Hero” integrates knowledge cards, role-playing, and AR technology, allowing children to learn about climate change through interactive experiences while enhancing their sense of environmental responsibility.