At some point in the past, during the conflict known as the Westchester War, Magneto and his Brotherhood of Evil Mutants declared war on humanity. The X-Men stopped them, and helped humanity realize not every mutant was a threat. Magneto died after years of fighting, leading an abundance of violent and uncontrolled mutants. The Westchester Treaty led to the creation of the Bureau of Super-Powers, an agency directed by Cassandra Nova, who established Clear Mountain Institute as a center for rehabilitation of mutants.
In reality, Cassandra Nova was the Shadow King, who escaped from the Astral Plane and used a member of a gang as a vessel to find the ruins of Apocalypse's lab, where he discovered a female clone body of Professor X in a stasis tube. When the Shadow King started inhabited the cloned body, the telephatic abilities let him sense the millions of souls in Battleworld, specially those of the mutants from other domains, such as the Monarchy of M, the Domain of Apocalypse, and the Sentinel Territories. The Shadow King realized that in comparison to those other domains, Westchester was a fragile paradise, and set out to ensure its survival by any means. Using the cloned body of Professor X, the Shadow King became Cassandra Nova, and used his new identity to become a politician and establish the Bureau of Super-Powers.
At the Clear Mountain, Cassandra Nova used a form of psychotherapy called the "Mind Field" to brainwash those mutants who arrived to the institute and force them to live in harmony. After defending themselves from an attack of renegade Free Range Sentinels, the X-Men found out about the Clear Mountain Project from Baron Kelly. The team decided to investigate and paid the institute a visit. After the tour, Cassandra Nova tricked them into trying the Mind Field, trapping them in a telepathically-created landscape. When Professor X decided to check on his X-Men by using the Astral Plane, the Shadow King detected him and attacked him, leaving him for dead.
While Nova used the Mind Field to test the X-Men, the X-Force arrived to the X-Mansion, having heed a telephatic call for help sent by Xavier before being attacked by Nova, and found his body. Psylocke discovered the Professor wasn't dead, and stayed at the Mansion, purifying his mind from Nova's infection while the rest of the team teleported to Clear Mountain Institute and attacked the building. Psylocke also used the traces of Nova's psychic energy to enter her mind field, where she rescued Cyclops and Jean Grey, whom Nova forced to tap into her Phoenix form. Professor X was finally able to regain consciousness, and informed Betsy that during Nova's attack in the Astral Plane, he was able to see into her plan and its next step, to assassinate Baron Kelly.
Psylocke and Professor X infiltrated the X-Museum to alert Kelly soon after the inauguration of a new exhibit. However, the Bureau of Super-Powers used news of the assault of the X-Force on Clear Mountain to make the X-Men appear to be the villains. Meanwhile, Storm was able to reach to her powers beyond the Mind Field and free herself, Scott and Jean from its grasp, joining the confrontation against Cassandra Nova and her brainwashed X-Men, composed of Gambit, Rogue and Wolverine. Back to the X-Museum, Professor X and Psylocke are being taken into custody when the Ten-Sentinel created to kill Kelly was unleashed to fulfill its purpose.
Cable's X-Force took Kelly to safety while the X-Men and some of the mutants from Clear Mountain, who had been freed from Nova's control, tackle the Ten-Sentinel. While Kelly was being transported to the Blackbird, Cassandra Nova intercepted him. Jean Grey tried to defeat her by channeling the Phoenix Force, but failed. Professor X appeared on the scene, where he unleashed the Onslaught for a final confrontation against the Shadow King.
While the Shadow King proved to be a strong opponent, Jean Grey, Cable, and Psylocke shared their power with Professor X. Meanwhile, Cassandra Nova, now freed from the Shadow King's possession, revealed a way to shut down the Ten-Sentinel, to use a laser beam to deliver shutdown codes to the giant machine. Gambit provided Jubilee with an opening to use a laser gun and shoot the Ten-Sentinel, successfully overriding its previous protocols and shutting it down. In the Astral Plane, Professor X was able to subdue the Shadow King and send him far away.
A few days after the events at the X-Museum, the Xavier school re-opened, with an ever-increasing number of new students, most of them who had been patients at the Clear Mountain Insitute. Cyclops and Jean Grey left for a vacation, leaving Storm the reins of the team. Cassandra Nova, who had fled from the battle against the Sentinel, was under the radar, and encountered Joseph in a cafe. And somewhere else, Baron Kelly met with his secret allies, Apocalypse and his Horsemen of Apocalypse, who were willing to share their evil plans for Westchester.
At some point, following her consecutive failed attempts to make the population of Battleworld submit to Doom, Mill-E the Model Citizen was given one more chance to accomplish her mission by the Council of Doombots, however, she failed yet again. Furious, Doombot Prime took control of her body and attacked Westchester's inhabitants. Soon afterwards, Mill-E was sent over the Shield to work in the Deadlands as her punishment.
Points of Interest
- Baron Robert Kelly
- Brotherhood of Evil Mutants
- Multiple Man (James Madrox)
- Iceman (Bobby Drake)
- Frenzy (Joanna Cargill)
- Havok (Alex Summers)
- Boom-Boom (Tabitha Smith)
- Polaris (Lorna Dane)
- Firestar (Angel Jones)
- Fabian Cortez
- 10 Appearances of Westchester (Battleworld)
- 2 Minor Appearances of Westchester (Battleworld)
- Media Westchester (Battleworld) was Mentioned in
- 5 Images featuring Westchester (Battleworld)
- Location Gallery: Westchester (Battleworld)