Sub-Mariner is a fictional superhero appearing in comic books published by Marvel Comics. Created by writer Bill Everett in 1939, he is the prince of the underwater city of Atlantis. Sub-Mariner possesses superhuman strength, the ability to fly, and can breathe underwater, making him a formidable character in both oceanic and surface battles. As a character, Sub-Mariner often finds himself torn between his loyalty to his underwater kingdom and his interactions with the surface world. He has been a member of various superhero teams, including the Avengers and the Invaders, and is known for his complex personality and fierce protectiveness of his home.