Wow this is the kinda game I wish I could make in a week, let alone 3 days! Well done for not only making finished game but also a good one. I like the non-literal interpretation of the theme, diving deeper into the past of the main character is more interesting than the ocean or mining.
Only problem I had, is that it is easy to fall off the edge of the world when exploring. Some colliders would have solved that. Although, I had no problems when sticking to the main path and it was overall a fun experience.