Origin[]

While Emma Frost lay in a comatose state, Dr. John Sublime harvested eggs from her to begin experimentation. The Weapon Plus program then used the eggs to create thousands of identical mutant girls in the hope of developing a powerful weapon capable of killing every mutant on Earth by combining their telepathic abilities. The project was designated Weapon XIV, and the girls were incubated and artificially aged inside the subterranean level of The World.^[6] While most girls remained dormant, five were sent to infiltrate the Xavier Institute as student sisters to hone their talents for Sublime's purpose.^[12][13]

Xavier Institute[]

After the Xavier Institute went public,^[14] Sophie and her sisters were enrolled as orphan quintuplet sisters.^[13] To protect their secret origins, the girls unconsciously placed mental blocks in the minds of the faculty preventing them from investigating their background.^[15]

The girls quickly gained the moniker "The Stepford Cuckoos", though their chosen codename was the Five-In-One. Emma Frost took a special interest in the girls, and the Cuckoos became her protégés.^[16][17]

Death[]

Much to her disapproval, the girls' rival, Quentin Quire (Kid Omega), developed a crush on Sophie. Sparked by Sophie's rejection, learning that he was adopted, his uncontrolled powers, and fueled by use of the drug Kick, Kid Omega led a rebellion of students at the X-Mansion. To stop Kid Omega and his Omega Gang, Sophie and the other Cuckoos covertly snuck into Cerebra. Using Kick to amp up her powers, Sophie and her sisters were able to stop Quire. Unfortunately, Sophie died in the process.^[3] Unbeknownst to the others, Sophie was actually being influenced into these actions by Esme, who was also using Kick.^[18][19]

Resurrection[]

When the Phoenix Force returned to Earth in search of a new host, Kid Omega was awakened. Still in love with Sophie, Kid Omega exhumed her in hopes of reuniting.^[1][20] However, upon her resurrection, she promptly rejected Quire and died once again.^[4]

When an unstable fraction of the Phoenix Force sparked inside the girls, their dormant Weapon Plus nanotech inside their bones was activated. This nanotech briefly reanimated Sophie and Esme, who directed their sisters back to The World to activate Sublime's plan for the destruction of the mutant race. Sophie and Esme were later killed by Celeste wielding the Phoenix.^[21]

Chaos War[]

When the Chaos King put the living asleep and opened the underworld, Sophie, Esme, Thunderbird, Banshee, Moira MacTaggert, and several dupes of Multiple Man were among the resurrected. Sophie confronted Esme about her death with little resolution. While searching for answers among the remains of the Xavier Institute, the former X-Men were attacked by the Carrion Crow. Sophie sacrificed herself to save the others,^[7] and Esme later sacrificed herself to save her sister. As she and John Proudstar faded back into the afterlife, John mused perhaps that next time he was resurrected, he and Sophie would be together. Sophie replied that she liked the idea.^[8]

House of X[]

Sophie was at some point resurrected by a group of mutants known as “the Five” (Eva Bell, Proteus, Hope Summers, Elixir, and Egg).

She was living on the sovereign nation state of Krakoa for mutants, created by Charles Xavier, Magneto, and Moira X. The Stepford Cuckoos and Magneto welcome a delegation of international ambassadors and representatives to give them a quick tour of this new world (showing them the new Jerusalem Habitat) while setting the terms of the new mutant state and its relationship to humanity.^[22]

Sophie is a mutant with psychically based powers similar to her biological mother, Emma Frost. Sophie's powers are identical to that of her sisters, though she was the strongest among them.^[17][7]

• Telepathic Hive Mind: Sophie has a linked hive mind with her sisters, which allows them to share thoughts and maintain a continuous telepathic connection. This mental phalanx also allows for increased telepathic strength and shared intellect.
  • Telepathy: Sophie can read minds and project her thoughts to others. Though she individually possess her own telepathy, her telepathic abilities are greater when the girls join together.^[23] The sisters have stated that together they can block even very talented telepaths from reading their minds.^[24]
    • Illusions: She can create realistic psychic illusions and cause people to experience events which are not actually occurring.^[5][25]
    • Mind Alteration: She is able to alter the minds of others by force of will. This can be restoring memories^[26] or transferring knowledge.^[27]
    • Telepathic Tracking: Sophie's psionic senses enable her to detect and track other sentient beings by their unique psionic emanations or thought patterns. This ability is highly sensitive to proximity, but can be enhanced with the use of Cerebra.
    • Astral Projection: Sophie is capable of sending astral projections, astral travel, and communicating with others astrally through her own will, or through contact with the thoughts and memories of others.
    • Paralysis: She is able to effect certain areas of the brain to induce temporary mental or physical paralysis.
    • Memory Erasure and Restoration: She can erase any awareness of particular memories or cause total amnesia.^[24] She can also restore memories.^[26]
    • Mental Triangulation: Due to her hive mind, Sophie has the perspective of multiple directions and is able to triangulate on individuals' minds.^[28]
  • Gestalt Psychic Link: Sophie and her sisters share ability to merge their psionic engrams together and merge individual telepathic powers as one enables the acquisition of far greater psychic capability than the sum of its parts. Sophie was the dominant consciousness and often commanded the Cuckoos governing their every action and deed.^[17][7]
    • Hive Intelligence: Sophie's intelligence gradually increases when she is in close proximity of one another, mainly when they are in the presence of another Cuckoo.
• Telekinesis: Like her sisters, Sophie possess psychokinesis of an undefined degree.^[29]
• Flawless Organic Diamond Form: Like their biological mother, Sophie has the ability to transform her body into a flexible, translucent, organic diamond-like substance while retaining mobility. In this form, her skin is as hard as real diamond.^[30][26]
  • Superhuman Strength: In diamond form she can lift 85 tons.^{[citation needed]}
  • Superhuman Stamina: Her diamond form grants her the ability to sustain peak exertion for up to a day.^{[citation needed]}
  • Superhuman Durability: Sophie's diamond form augments her skin, bone, and muscle to become stronger and harder than human. She is completely impervious in her diamond form.
  • Compartmental Diamond Transformation: Unlike Emma, Sophie and her sisters can selectively transform discrete parts of their bodies. Once, to trap the Phoenix Force fragments, the girls transformed their hearts into a flawless diamond prison.^[31]

• Kick

• Both Sophie and her sisters have mentioned that she always had a desire to be a hero.^[3][5]

• Sophie was the most powerful among her sisters.^[17][7]
• Sophie is buried in the Xavier Institute cemetery, and her tombstone reads "Sophie - One of Five - Heroine of Open Day".^[1]