As far as apocalyptic events go, zombie invasions rank among the most horrific of all the possibilities. Now add into the mix zombified versions of Marvel's most famous superheroes -- who retain their intellect, personalities, and superpowers -- and you have a truly nightmarish situation. This is exactly what happened in Robert Kirkman and Sean Phillips Marvel Zombies miniseries, which introduced us to Earth-2149, a world where the earth was overrun by a zombie virus. While that might seem like the peak of how bad the situation could get, the series found a way to make things way worse than simply zombified versions of your favorite superheroes.
After the majority of Avengers, X-Men, and Fantastic Four members are all infected with a virus that turns them into zombies, the Silver Surfer arrives on the now post-apocalyptic Earth-2149 to herald in the arrival of his master Galactus. Now that earth no longer contains any living beings, Galactus can finally devour the now desolate planet. Initially, the Surfer successfully avoids being harmed by and of the zombies, until the Hulk arrives and bites his head off. After his death the Surfer is split amongst -- and devoured by -- Colonel America, Iron Man, Giant-Man, Spider-Man, Luke Cage, the Hulk and Wolverine who acquire a portion of his power cosmic and slaughter the remaining zombies.
After a subplot reveals that Black Panther and some other heroes are still alive, Galactus arrives on the planet. The zombified heroes, no longer satisfied by the flesh of other zombies as a source of food, rush the world eater in hopes of making him their next meal. However, despite receiving a boost from the power cosmic, Galactus repels his attackers easily. This defeat leads the zombified Giant-Man, Iron Man, and Bruce Banner to create a device that amplifies their newfound cosmic powers in hopes of taking down their long time enemy whose role has been flipped is now the univere's last hope at stopping the former heroes.
The zombified heroes manage to injure Galactus, but are sidetracked and forced to find zombified versions of their major villains. While Colonel America is killed by a zombified Red Skull, the rest of the zombified heroes manage to fend off the zombified villains before finally taking down Galactus and devouring the world eater once and for all. After eating Galactus the zombified heroes are infused with the rest of his power cosmic, turning the former heroes into a new twisted and dark version of the Avengers, the Galacti. The ending of the series reveals the Galacti have taken their hunger for flesh to the stars, as they are shown to arrive on an unknown alien world to devour their population.