Spiral

Now this woman is hands full with mischief. 

Spiral intermittently serves as the right hand—no pun intended—of Mojo, also known as Marvel comics' megalomaniacal dead-ringer for Jabba the Hutt. She had been an ordinary human named Ricochet Rita when Mojo held her captive and modified her into a semi-cybernetic, living Shiva. Like the Hindu god, Spiral often dances to bring out her powers, which straddle magic and technology. 

Spiral has racked up atrocity after atrocity at the bidding of Mojo, who runs a TV-like network in Mojo World. On her own Spiral has proved to be just as fearsome. For some time, Spiral ran a business on Earth called the Body Shoppe (not that Body Shop), where she installed cybernetic body parts on people—if not made them cyborgs altogether. Lady Deathstrike was one satisfied customer. 

By her own initiative, Spiral virtually made a soap opera out of Psylocke's life, who had otherwise starred in a Mojo-produced TV show on a separate occasion. Spiral switched Psylocke's body with that of an Asian assassin named Kwannon, making for one intriguing X-Men story arc in the 90s.

Face/Off has nothing on this.

But this is not your normal Freaky Friday switcheroo. Spiral made the swap such that both would have some traits of the other, rendering them indistinguishable. Eventually Kwannon, now known as Revanche, contracted the fatal Legacy Virus.  

BURN BITCH. No amount of sword-fighting 

could return Psylocke to her body now.

So long as Spiral stays obsessed with human anatomy, the Marvel universe would always get more convoluted than it already is. This intergalactic madwoman certainly has much time in her hands to devise more schemes. Chaos and confusion, after all, come with the territory of six arms.