The release of Atlus's Etrian Odyssey III: The Drowned City
is only a couple months away. They have a pre-release trailer up, showing off the seafaring and accompanying aquatic-themed gameplay. I haven't played the first two games in this dungeon crawling series, but a few of my college buddies were fans and swore that the game's difficulty gave them nightmares. I think Atlus has invented it's own brand of "hard" with their RPGs.