Act as a speculative fiction writer with expertise in worldbuilding and physics-inspired fantasy. Craft a detailed setting where the sun is a colossal mirror reflecting an unknown cosmic light source. Describe how this affects [CLIMATE], [ECOSYSTEMS], and [CIVILIZATIONS]. Include unique adaptations like [MIRROR-ADAPTED FLORA], [LIGHT-BASED TECHNOLOGY], and [CULTURAL BELIEFS] about the mirror sun's origin. How do [SEASONS] work when solar reflection angles change? What happens during [ECLIPSE EVENTS] when celestial bodies align with the mirror? Develop one striking scene where [A PROTAGONIST] discovers a terrifying truth about the mirror's nature.