This is a short(ish) little explanation and depiction of a recently added mechanic: upgrading your ghost!
So at the beginning of Why Am I Dead At Sea, you begin as a small little wisp clinging desperately onto your existence. You have no recollection of who you were in your past life, much less how your death came about.
Oh, to be human again...to have legs, arms...dare one even hope for a face? Well, now it's possible. Throughout Why Am I Dead At Sea hide clues to who you were before your death: the type of person you were, how you ended up on the boat in the first place, and how you got along with the other characters. The more you discover, the more your identity pieces together.
And as your identity comes together, you transform from a little wisp back to a proper ghost!
Okay, so it's nice to figure out who you were pre-mortem...how does this help you answer the ultimate question: why you are dead? Well, it's quite simple. Up to this point, you've had an arsenal of tools to gather information - reading minds, influencing people, and fully controlling them. But as your identity strengthens, so does your presence in the physical world. You will ultimately be able to appear before the characters of the game, if only briefly.
Now, everyone will react to these hauntings differently. Some may recognize you, but some will mistake your visage for another person they have on their mind. You still aren't able to have conversations with people, so more skeptical, grounded people will dismiss the event or try and explain it away. Even so, these interactions will often reveal something about the person in question, and may on occasion reveal much, much more.