Cassandra Nova

In Marvel Comics continuity Cassandra is a mummudrai — a parasitic life form born bodiless on the astral plane. In the published narrative she co-existed in utero with Charles Xavier; Xavier recognized an evil presence and, by the account given in the sources, killed the entity in the womb resulting in her stillbirth. The mummudrai that became Cassandra became telepathically entangled with Xavier, gained psionic abilities, exited the womb, and copied Xavier's DNA to form a physical body in order to seek revenge.

Sources emphasize Cassandra's ability to create or take bodies rather than a single canonical physical description. Canonical accounts state she copied Xavier's DNA to make her own body, later switched into Xavier's body, and at other times occupied or controlled human agents (e.g., Donald Trask III). Different continuities and adaptations portray her appearance variably (comics portrayals across storylines; a film adaptation places her as ruler of the Void), but the supplied sources do not supply a single definitive set of sustained facial or clothing details.

According to the documented sources Cassandra can access the full spectrum of latent mutant functions present in Charles Xavier's genome, granting her vast psionic powers. Explicitly named abilities include telepathy, telekinesis, intangibility, astral manipulation, mental possession, and the power to copy DNA to create bodies. She has demonstrated advanced telepathic stealth (hiding possession from other telepaths), rapid bodily healing via self-manipulation, the ability to manipulate humans and technology (notably manipulating Donald Trask to deploy Wild Sentinels), and large-scale violence (responsibility for the massacre of 16 million mutants on Genosha).