While it is true that Maku can transform himself into a Merwolf, that is not all that he can do. He has learn how to harness the powers of water around him, even when he is swimming underwater. Here, he is using his powers to create a cloak like wave as a part of his dance's that he enjoys doing.

You do not believe how much I was amazed at seeing this pic that Diana did for me! I love how it turned out and it was worth every penny I have!