Ultimate Galactus Trilogy

A broadcast disrupts the world's communications systems, filling televisions and computer monitors with images of death and destruction that cause thousands of people to commit suicide. The broadcast ripples across the psychic plane, and attracts the attention of S.H.I.E.L.D. and Charles Xavier, with both tracing the source to the Tunguska wasteland in Russia, the site of a massive comet crash over a century ago. S.H.I.E.L.D. Commander Nick Fury leads a team of heroes - Captain America, Black Widow and Sam "Falcon" Wilson - on a reconnaissance mission, while Professor X sends the X-Men Jean Grey, Wolverine and Colossus to investigate. Neither team is aware of the other's involvement.

The two teams trace the signal to an abandoned complex built in the era of the Soviet Union and encounter an army of mutated humans, all engineered by a now-defunct Soviet super-soldier project designed to create versions of Captain America. Two characters who make appearances, though unnamed, are Ultimate Unicorn and an Ultimate version of Red Guardian. After defeating the humans the two teams meet, with Fury's team capturing the X-Men and then discovering the source of the broadcast - a sentient, self-repairing robot called Vision. Vision explains that it traveled to Earth 100 years ago, and when its ship malfunctioned it crashed in Tunguska and was later captured by the Soviets, who amputated portions of its body and grafted them onto Soviet Army volunteers to create experimental super-soldiers. Vision has repaired itself enough to communicate with the world and warns Fury of an impending threat: the Eater of Worlds called Gah Lak Tus. The X-Men subsequently escape and Fury's team takes the Vision back to S.H.I.E.L.D for further analysis.

The cover of Ultimate Extinction #5 (July 2006), featuring the Gah Lak Tus swarm. Cover art by Brandon Peterson

A secret S.H.I.E.L.D. installation in New Mexico investigating revolutionary methods of space travel is attacked by the alien Kree. This forces resident scientist Dr. Philip Lawson to change to his true identity of Captain Mahr Vehl and battle the attackers. Although able to successfully defend the installation, Mahr Vehl is rendered unconscious and is eventually questioned by Fury. Mahr Vehl explains he is a member of the Kree himself, and that they have been observing Earth to determine if humanity poses a threat to the Kree in the larger galaxy. Observing mankind's violent nature, Mahr Vehl reveals that the Kree have recently decided to confine humanity on Earth until the entity Gah Lak Tus can destroy them, thus ending the potential threat. Realizing that other Kree will be coming and that the threat the Vision foretold is now very real, Fury summons the Fantastic Four and the Ultimates.

A Kree force attacks the installation soon after but is stopped by a combined team of heroes. Another team of heroes - with Mahr Vehl's aid - storm the Kree ship while the aliens are on Earth. The commander, Yahn Rgg, activates the self-destruct mechanism, but not before Mahr Vehl hacks into the ship's database and downloads its contents into his memory banks. With the information gained from both Vision and the Kree, Fury contemplates how to deal with the coming threat of Gah Lak Tus.

Fury enlists the aid of Reed Richards and Professor Xavier once Silver Surfer arrives to "herald" the approach of Gah Lak Tus, who is discovered to be a swarm of thousands of sentient ships stretched 100,000 miles (160,000 km) long and within only a week's journey from Earth.

The heroes Captain America, Falcon, Iron Man and Mahr Vehl have several battles with Gah Lak Tus' heralds, the Silver Men, and allow Reed Richards, Charles Xavier and Jean Grey time to develop a plan. Xavier and Grey make psychic contact with Gah Lak Tus, which completely repulses the entity and distracts it. Richards then uses a weapon known as the "Nevada gun" and teleports the latent energy of a Big Bang into the heart of the Gah Lak Tus swarm. With 20% of its mass destroyed by the blast, the entity retreats. Richards then programs Vision with plans for the weapon and sends it into space, in the hopes that other races will be able to benefit and fend off Gah Lak Tus. Nick Fury's only comment on the matter is "the human race can kick the hell out of anything."