If you were in any doubt as to the centrality of naval combat/shenanigans to Assassin's Creed 4: Black Flag, check out the below shots and consign those doubts to Davey Jones's Locker, which could probably do with a clean.... read more
Also why do I find screen #6 highly implausible when the entire game revolves around hacking our brains to live the lives of our ancestors for some reason which ignores how they could have just wrote down the things people are looking for, yeah there's a magic door somewhere, instead of passing this on we'll just pass on that we're assassins and Templars are bad. No I find swimming with a hat on much more silly.
...and if you tell that to the kids of today, they wont believe you!
They're Official Marketing Screenshots, so PC with lots of spit and polish I expect. Can't help you with the writing thing and the underwater hat-wearing, but I'll be sure to bring it up in an interview.