Greatest Villains of All-Time: Cassandra Nova
The Search for the Greatest Villain of All-Time
The Mummudrai are a parasitic species born bodiless on the astral plane. Within the womb of Charles Xavier’s mother, this parasite materialized a body by feeding off of Charles’ developing telepathic abilities, effectively becoming his twin sister. But even the unborn Xavier could sense Cassandra’s monstrous thoughts and attempted to kill the creature by strangling her with his umbilical cord. While this incident left her fetus to be considered stillborn, Nova actually survived as chaotic cellular matter. Over the next several decades, she would rebuild her physical form while perfecting her effort to mimic human traits. During this time, she grew convinced that the womb in which she had fought Charles and the universe she now inhabited were one and the same, a universe in which only she and Charles were real, and that her purpose was to destroy every illusion Charles held dear.
She is the ideological dark shadow of Xavier and is hellbent on destruction and genocide.
E for Extinction
Her biggest atrocity by far is the Genosha genocide.
Because Professor X envisioned a world where humans and mutants lived in peace, she knew there was no better way to exact her revenge than to crush that dream. She convinced the last living relative of Bolivar Trask, Donald Trask III, to activate a pair of enormous Wild Sentinels and send them to destroy the mutant island of Genosha, killing 16 million mutants.
In a single assault, she brought mutant kind to the brink of extinction.
Cassandra duplicated Trask's DNA so she could also issue orders to the Sentinels, programmed to obey only those with the DNA of a Trask. Cassandra infected her own body with millions of Nano-Sentinels before allowing herself to be captured by Cyclops and Wolverine and taken to the X-Mansion.
With a Vengeance
After breaking free and easily defeating most of the X-Men in the mansion, Cassandra made her way to Xavier's machine, Cerebra (an enhanced version of Cerebro), in an attempt to destroy all mutants. As she entered the machine, Emma Frost snapped her neck (Emma was at Genosha teaching during the attack and witnessed her students massacred) and was shot multiple times by Xavier. What they didn’t know was that Cassandra managed to switch minds with Xavier. Once in Xavier's body, she exposes him as a mutant to the world, and mentally forces one of the institute’s students to beat Beast into a coma after he discovered that Xavier and Cassandra shared the same DNA.
She later planned on using Cerebra again to eliminate all mutants. However, Jean Grey (who was becoming increasingly powerful due to the manifestation of The Phoenix) was able to split Xavier's consciousness into pieces and store a small part of him in the minds of every living mutant. When Cassandra used Cerebra and focused on all the mutants, the pieces of Xavier's mind were brought back together, and forced her out of his body. Without a body, Nova became pure psychic energy, at which point Emma Frost tricked her into returning to what appeared to be her old body but was in fact the alien polymorph "Stuff." In a last act of desperation, Nova used her powers to essentially inception Emma Frost, who eventually tortured the X-Men with illusions and tricked Kitty Pryde into releasing Cassandra.
Nova would go on to stoke anti-mutant hate through psychic suggestion and set up world governments to attack mutants everywhere. Infecting people with an updated version of the Nano-Sentinels that could place anyone under her control and allow normal humans to detect the presence of the X-Gene, while also sending them into a murderous rage.
Cassandra Nova is, without question, one of the most dangerous figures the X-Men have ever encountered, and one of the most personal.
