The Moving Island

There is a myth of a creature known as the Zaratan that is told by a crazed local Water Genasi in the town of Wasu. The story goes like this...
"I was out on a normal fishing trip in my grandfathers old boat when a mighty storm hit out of nowhere! With the ocean rapidly forming into humongous swells, wind tearing at my sails trying to rip them of my vessel, I struggled to shape the water to bring me back to shore. Large cracks of lightning began to streak the sky as I struggled to keep my vessel from being torn apart."
"suddenly out of nowhere a large crack and a boom sounded above me as lightning struck my poor old grandfathers boat. The next gale of wind blew off the top sail which whipped around and caught me by the ankle. I tried I did to escape but alas I was drug down and hit my head before falling unconscious into the ocean."
"Next thing I know I'm awake, but not seeing the watery grace of The Healer, nigh. Instead I'm covered in sand and seaweed with a head that ached of all the devils themselves! Looking around I noticed that I was on an island of some sort and even yet, the island was moving! I could tell by very very small wakes, almost unnoticeable coming from the west end of the island. I made quite the living on that moving island however until one day it slammed into something I didn't see. The force was unbelievably strong and my poor makeshift house was destroyed along with most of the things I had procured."
"The island didn't move much after that and I stayed, oh I dont know maybe several months longer, it's hard to tell and I lost count all by my lonesome. Anyways one day a ship came by and I called to them with large spouts of water I shaped where they came to get me. They thought I was crazy they did, didn't believe a word of it but I tell you it's true tis is."
"There are islands in these magical oceans that move with the force of The Great Collosi I tell you."