The Silver Surfer who is involved in the Second Kree-Skrull War temporarily lost control of his board due to space fungus. He used the Power Cosmic to restore the space fungus to its previous form, that of the Deviant Ghaur. Who realizing he would likely lose a fight with the Silver Surfer headed back to Earth. The Silver Surfer preoccupied with the intergalactic war, sent a mental warning to Doctor Strange. Upon his arrival on Earth, Ghaur arrived in the undersea dominion of Lemuria and recruited Llyra. He planned to locate the Serpent Crown to summon the Elder God Set, to destroy his enemies on Earth.
In a meeting with Attuma at a Lemurian rebel outpost, Ghaur explained to him his plan to take over the world. In which they would use the combined forces of Attuma's Atlantean army, Llyra's Lemurian rebels, and Ghaur's Deviants to prepare the world for Set's return by weakening the surface world. Attuma agreed on the condition that he be put in command of the combined military forces. Namor working with Iron Man in investigating a Hydra operation, discovered Attuma's forces sneaking into the Panama Canal. Battle ensued between the invaders and the heroes. They held off the invasion force until the U.S. Air Force arrived.
Lyra and Ghaur relocated to the Bermuda Triangle, establishing a base on Magneto's former island. Where they prepared to summon Set by recreating the Serpent Crown. The Abomination, whose body was inhabited by Tyrannus was freed by Lemurian soldiers. Ghaur and Llyra were able to pull his mind out and restore his body.
Back on the island base in the Bermuda Triangle, Ghaur was building a giant version of the Serpent Crown. Meanwhile Viper and Tyrannus were creating Serpent-Men. Ghaur ordered an attack on the surface world. Attuma sent his lieutenants (U-Man, Tyrak, Lord Arno, and Warlord Krang) to attack the American eastboard, each of the four leading an army. Which attacked the Shoreham Nuclear Plant, Langley Air Force Base, Fort Hamilton Army Base, and Cape Canaveral. In response to the attacks, Captain America assembled the Avengers who split into four teams which engaged and defeat the invaders.
A team of Deviants who looked similar to several New Mutants members were sent to retrieve the Horn of Doom. Despite the assistance of the Atlantean mutant team SURF, Namorita was unable to stop them. Mistakenly believing the New Mutants were the attackers, they went after the New Mutants and attacked the teens. While they fought, Ghaur used the horn to summon an undersea monster to attack Atlantis as a sacrifice to Set, thereby betraying his Atlantean allies. The New Warriors, Namorita, and SURF joined forces to save Atlantis by leading the monster away from Atlantis into a trench where they buried it, though by that time the city was in ruins.
As Marvel Girl hurtled toward Ghaur's base, pulled by a tractor beam as she was one of several female super-heroes whom Ghaur had marked with the "Mark of Set", Beast hanging on to her ankle. He managed to break through her trance, dropping them into the ocean. Attuma decided he would claim her and took his army to retrieve her, where he encountered Atlantean rebels led by his daughter Andromeda who challenged him to a duel. A battle ensues between the two forces. Beast attempts to rescue her with the assistance of his former teammates, the Defenders. To prevent Jean Grey from dying he was forced to turn her over to Ghaur. Attuma defeated Andromeda, and Ghaur snatched her before he could end her life, to make her one of the Brides of Set.
Attuma personally lead the Atlantean attack on New York City, where they did battle with the Fantastic Four, Spider-Man, and the US military. Who were able to hold off the Atlantean forces until they sent in a giant monster, the Megasaur which turned the tide in their favor until it was defeated by Spider-Man. While this was going on, the undefended city of Atlantis was destroyed by Llyra's Lemurian forces. Ghaur has taken the Invisible Woman captive and the disguised Namor assisted in the defense of NY City. Upon learning of the betrayal and the destruction of Atlantis, the Atlantean army retreated back into the ocean and a stunned Attuma surrendered without a fight.
As his plan to have the Atlanteans sacrificed to Set failed, Ghaur sent his marked female captives (the Seven Brides of Set - Dagger, Storm, Marvel Girl, She-Hulk, Andromeda, Scarlet Witch, and the Invisible Woman) to retrieve artifacts which he can use to summon the Elder God Set from the dimension in which he is imprisoned. She-Hulk is apprehended by Captain America, the West Coast Avengers, and Beast while the other brides achieved their objectives. They let her go and follow She-Hulk to the seas and back to Ghaur's base. Where they are forced to battle the Brides and the Deviant army. Wonder Man destroyed one of the artifacts and in desperation Ghaur ordered the Scarlet Witch to use her reality-warping abilities on one of the artifacts. Beast attempted to stop the spell using an iron gauntlet and failed, as Set breaks through to the material plane.
Thor, Doctor Strange, Quasar, and the Thing end up in Set's dimension where they fought the Elder God in his true form, an inside-out version of the colossal multi-headed snake. Thor goes to Gaea for help but she is contained by Set's growing power. He then headed to the Sun's center to summon Atum and managed to goad him to transform into Demogorge, the god-eater. Who consumed Thor, briefly permitting Thor to have some control over Demogorge. It appeared in Set's dimension, rips off Set's heads, and sent those seven heads into different dimensions. After which Demogorge spitted Thor out. Having been defeated, Ghaur disappeared before the Avengers can apprehend him.
The Fantastic Four, Avengers, and several other super heroes arrived at Llyra's underwater base. Defending it is was army of Lemurians and Deviants, which they battled. Ghaur attempted to summon Set by using the Seven Brides. Namor arrived and confronted Llyra and Ghaur, and was soon joined by the Fantastic Four. Together they fought Ghaur and Llyra, who are empowered by the Serpent Crown. When Ghaur betrayed Llyra and took her access to the Serpent Crown, the burst of power ended up summoning Naga's spirit. Who emerged and fought Ghaur for control of the Serpent Crown, which resulted in Naga, Ghaur, and Llyra apparently blinking out of existence. Freeing the Seven Brides from the Serpent Crown's control. Which became unstable and on the verge of exploding. The former brides pushed the Serpent Crown into a ravine where it exploded. Namor and his cousin Namorita then took off to find their people whom disbursed due to the destruction of Atlantis.