Green Heights is a first-person vertical platformer where the protagonist must scale sheer structures within a confined space reminiscent of a giant terrarium. The environment is imbued with a mystical atmosphere, created by deliberately aged textures and dim lighting that evokes a sense of unease. Dense vegetation conceals subtle loopholes that can significantly shorten the climb to an inaccessible summit. The exploration aspect is closely intertwined with the fear of making a fatal mistake, as any misstep instantly resets progress. The lack of intermediate checkpoints transforms the monotonous traversal of obstacles into a severe test of endurance, justifying the inclusion of psychological thriller elements.