Nano Banana Pro: [SHAPE]-shaped Cave Entrance in [TYPE] Landscape

Prompt on Nano Banana Pro: An image of a [TYPE] landscape, featuring a cave entrance that is shaped exactly like the outline of a [SHAPE]. The cave should blend naturally into the rugged terrain of the mountain, with the entrance forming a clear and unmistakable [SHAPE] shape. This [SHAPE] shape should be simple and defined, without intricate details, emphasizing just the overall [SHAPE] outline. The surrounding environment should include [DETAILS], but these elements should not distract from the shape.