Drowned in darkness, the crew is on the lookout for the slightest noise. Your captain braves the darkest depths, mapping unkonwn bottoms with new rare earth. All fear the surprises that these depths hold for them, which push the laws of nature to their boundaries. And the rumors... Some hear the rumbling of a great volcano, and dream of passages to a strange world... And now, a word haunts your hallways: "Hollow Earth." Join Operation Dragon, a campaign that will take your team to unexplored seas! Gain experience and hire Experts to help you during the game. Also enjoy the Custom Pack, allowing you to adapt any map from the Captain Sonar range to the play style you want. Armada mode, new stations... For an enhanced gaming experience!