This is a "Trick Question", not a "Quick Question" - right?

My experience with ships is limited,  I did some work on ships in small yards in Dutch Harbor, Alaska years ago.  That being said, I've worked with a lot of folks who have quite a bit of experience in large shipyards and have picked their brains.  In this day and age with technology being what it is, I'd say you could run into almost anything on a ship.  Up to and including an orbital process used.  I was offered a nice package last year to go to Seattle if I could TIG and SMAW high nickel content metals.  I turned it down in favor of a better job.  I notice you've asked earlier in the forum about types of welding to learn.  I will echo others opinions, the more certifications and process's you can learn the better of you'll be.  Also any other related skills will serve you well, such as pipe and or structural fitting and layout.  If you are well rounded in the trade and willing to work (and travel at times) the world is your oyster.  All that being said,  in my humble opinion there are a lot better places to work than a shipyard BUT they are a great place to start and develop skills that will take you as far as you want to go.  Best of luck to you

flux core

As you mentioned, as well as all the other major processes.