The mythological figure known for his ability to transform into different forms in Greek stories is Proteus. Often referred to as the "Old Man of the Sea," Proteus is associated with changing shapes and the fluidity of nature. His ability to morph illustrates the themes of adaptability and the elusive nature of truth. Proteus was known to foretell the future, but his transformation made it difficult for others to secure his knowledge. This myth reflects human struggles with the search for knowledge and the challenges that come with understanding an ever-changing world.