From the back of the book:
The earth’s oceans: vast, foreboding...but mysterious no more! Now you can explore the depths of Marvel Earth in this HUGE volume! Highlights include:
• A complete guide to the sunken lands of Atlantis, Lemuria, Mu, and more
• Profiles of dozens of characters suitable as Player Characters, Villains, and NPCs
• A full-sized map of the Atlantean city of Tha-Korr
• New talents, magic items, and equipment to get you on your way!
This latest book in the Marvel Superheroes Roleplaying Game Unofficial Canon Project’s Marvelous Locations series, helping you to detail the many realms and environments of Earth-616. Check it out!