Namor's next major love interest is the aquatic alien Marrina, a member of Canadian super-team Alpha Flight. Tragedy strikes this relationship as well when Marrina is forced to transform into her true form, a savage beast called Leviathan. Namor ends up having to slay her and never forgives himself for the deed.
Namora is the adult cousin of Namor and, in a reversal of Namor's heritage, she is the daughter of a human mother and Atlantean father. She fights alongside Namor until her apparent death at the hands of an evil Lemurian named Llyra. Years later, she reappears as part of the Agents of Atlas, a group of globe-hopping, old-school heroes.
Namorita is a younger clone of Namora. She poses as Namora's daughter, as cloning is illegal in Atlantean culture. She has the gift of flight like her relatives, and teams up with Namor many times, with the two forming a sibling-like bond. Namorita is also best known as a founding member of the New Warriors, alongside heroes like Nova, Night Thrasher, Justice, and Firestar.
Just after the Kree-Skrull War, several of Earth's greatest minds join together to create a secret group called the Illuminati. Their goal is to monitor other-dimensional and extraterrestrial incursions into Earth and stop them. Namor is a founding Illuminati member along with Reed Richards, Tony Stark, Professor Xavier, Doctor Strange, and Black Bolt. Namor eventually splits from the group after he makes the decision to destroy an alternate Earth that is threatening the prime Earth.
The Fantastic Four are among the earliest teams to count Namor as both a foe and an ally. While Johnny Storm first helps to restore Namor's memories, the rage at the seeming destruction of the Atlantean race leads Namor to launch an invasion of the surface world, with the Fantastic Four as the only ones that can stop him. Later, after Namor takes a romantic interest in Susan Storm, he becomes more of an ally to the team, even becoming a member of the Fantastic Four on a few occasions.
During World War II, Namor fights alongside Captain America, Bucky, and the original Human Torch as the Invaders, an Allied team designed to fight the Axis powers wherever they can.
When he is included in the Avengers lineup, Namor is met with numerous protests, as he is infamous for his attacks on humanity, Eventually, Namor manages to prove himself to the world and his teammates while retaking Avengers Mansion from the Masters of Evil and fighting the Olympian gods. He also manages to discover the underwater cocoon containing Jean Grey, once thought to have perished as Phoenix.