According to the packaging, the larger cards allow for larger ships and sea monsters. I have purchased three packs that contain these special edition cards and have three large cards that I want to feature here.
The Ghost Walker is a Wind Catcher, an experimental ship created by the top minds in the navel department. With its unique system of sails, it was created to keep watch on friends and foes so the top brass would be prepared for all future operations. Once per turn, one crew member or ship within a S of this ship cannot use their ability that turn.
The HMS Hermes is catamaran that gets to ignore terrain pieces like whirlpools, fog banks, reefs, or Sargresso Seas. This ship and her crew are tasked with scouting islands to look for pirate havens, and possible staging points and trading posts.
Shal-Bala, a sea dragon and has ties with the infamous Captain Davy Jones. It is hard to tell whether Shal-Bala is Jones pet or a partaker in Jones demented paths of destruction. Since Shal-Bala is a winged creature, she has unlimited access to anywhere on the board, whether it be land or sea.
Shal-Bala is feared by all. Only a few have lived to tell their stories about their encounters with Shal-Bala. Many who have lived to tell their stories have given up the sea and have retired to a monastery and do vespers.