Search for Okuna Longtusk.
<You open the bottle and find a message inside.> Help! I need somebody... but not just anybody. I need a champion! I finally escaped the grasp of Prince Oceanus only to be hunted by his father, King Deepbeard. I was enjoying my freedom and decided to go fishing when that giant attacked. I've been running around these islands trying to avoid that creature ever since... if anyone gets this message, please send help!