It's coming soon from IDW Games.
From the announcement:
‘Arrrrrrrrm yourself with a whole new set of powerful encounters in this new expansion brought to you by Jamie Keddie, designer of the original Random Encounter card game. This time around, the incredible retro-pixelrific art is nautically themed with favorites like giant man-eating clams, sirens, a clan of Vikings, and a baby on a seahorse, to name a few. And what would the game be without a progressively fatter series of sea chickens? The question is… what do sea chickens eat? And how do they get so big??