What crept among the leaves What is strange about the phrase used?

The phrase "what crept among the leaves" evokes a sense of mystery and intrigue, suggesting something hidden or stealthy moving through nature. Its strangeness lies in the use of "what" instead of a more specific subject, creating ambiguity about the creature or entity in question. This choice adds to the suspense and invites the reader to ponder the unknown, enhancing the overall atmosphere of the scene.