The ocean provides a home for countless creatures to survive and reproduce. In such a vast and deep space, beautiful, strange, ancient and changeable creatures on the earth are concentrated. Some of these "elves" living in the ocean live cautiously in muddy and wetland sand pits, alternating between day and night with the ebb and flow of the tide; some are ferocious and extraordinary, showing the style of predators; others swim and play in groups, creating beautiful scenery in the shallow sea area. Come into the blue home and get to know these wonderful ocean "elves"!