These MasterPieces 15" x 21" 500pc Hidden Image Glow-in-the-Dark Puzzles feature various ocean and wildlife scenes, each with special, hidden animals or objects, some of which glow-in-the-dark, and others who hide in plain sight. Find amazing unicorns in the secret retreat of the Unicorn kingdom. Find all the secrets in these wildly entertaining puzzles! To reduce their impact on our environment, the chipboard used in these puzzles is made of recycled material.