Marvel Universe/M

Mark Hallett
Mark Hallett is a mutant who also goes by the name of Sunder. He is an immense, muscular bald man who is the loyal, yet somewhat dimwitted lieutenant of Callisto of the Morlocks. Sunder was responsible for kidnapping Warren Worthington, III, which led to the Morlocks' first encounter with the X-Men. Mark was a survivor of the Mutant Massacre and later became a member of the short-lived adjunct X-Men team based out of Muir Island.

Mary Jane Watson
Mary Jane Watson is the ultimate fun girl. She's done it all: Model, dancer, soap opera star. Mary Jane has been a close friend of Peter Parker for many years. She dated Peter's best friend Harry Osborn for a time, but eventually broke up with him, causing Harry to turn to drugs. She began dating Peter Parker, deducing for herself that Pete was actually the wall-crawler known as Spider-Man. After college, Mary Jane tried to make it as an actress and played a recurring role on a soap opera. Her relationship with Peter grew stronger and she revealed that she knew the truth about him. Despite the hardships of loving a superhero, Mary Jane and Peter Parker tied the knot. All of that ended however after a reality-altering deal with Mephisto warped events, making it so that they never got together.

Masque
Masque is a member of the Morlocks. Masque's gender has never been completely clarified, but he is generally regarded as being male. Part of this confusion stems from his mutant ability to alter the physical characteristics of biological material, shifting the shape, color and contours of people's faces, including his own. Masque was always one of the most ambitious members of the Morlocks, and eventually became their leader after Storm dissolved her association with the group. For a time, it was believed Masque had been killed by Shatterstar during a fight with X-Force. Masque survived however and returned some time later to form his own group of mutant outcasts, The Tunnelers.

Mephisto
Mephisto is an arch-demon of Hell. He has often been regarded as the one true Satan and holds the highest authoritative rank amongst all demons. Mephisto brokered a deal with motorcycle stunt rider Johnny Blaze to save the life of his mentor Crash Simpson in exchange for servitude. As a result, Blaze was forced to become the demonic agent known as Ghost Rider. Mephisto tendered a similar bargain to Peter Parker in order to save the life of Peter's aunt, May Parker. To save May, Peter's marriage to Mary Jane Watson was erased from reality.

Misty Knight
Mercedes "Misty" Knight was once a police officer for the New York City Police Department until she was gravely injured on the job, resulting in the loss of her arm. She befriended Colleen Wing and founded a private investigation firm known as Nightwing Investigations. Studying in Eastern martial arts, Misty and Colleen took to calling themselves the Daughters of the Dragon. They were close allies with Power Man and Iron Fist, who ran their own agency, Heroes for Hire. Misty entered into a romantic relationship with Iron Fist, which ended upon his apparent death. Afterward, she became involved with a man named Tyrone King, unaware that he was actually Iron Fist's old enemy, Master Khan. Years later, Misty and Colleen reformed a new brand of Heroes for Hire. She also became a member of the all-female team of adventurers known as the Fearless Defenders.