Ghostbeard

Ghostbeard is the Twelveth boss you will face and its element is Spirit/Water so it is weak against Fire/Wind and it is strong against Earth/Fire. You can face it in the Sunken Carrack  or at the Summoning Stone. If you beat it 10 times, you will get the achievement Pirate Conqueror. It drops Ghostly Beard Hairs which can be used to craft Spectral Captain's Uniform  or Typhoon Gems which can be used to craft Atlantean Avenger Armor. Beating Ghostbeard on Epic stage gives access to the Misty Marsh.