X-Men's new team-up with Spider-Man identifies who their worst villains are
The tragic history of Madelyne Pryor's life, retold in the current dark web event, easily proves that Mister Sinister is the worst villain in the X-Men.

Warning: Contains spoilers for Dark Web: X-Men #2
As the events of the Dark Web - the diabolical crossover between the X-Men and Spider-Man - continue to escalate, the prominence of Madeleine Pryor's traumatic creation and life history easily proves that Mister Marvel is one of the worst villains in Marvel Comics 1.
Of course, Mister Sinister has always been a villain, and even when he's "done good", it's always under the guise of selfishness that somehow benefits his own agenda and plans for domination. However, the X-Men have a myriad of enemies - some of them downright terrifying - so the fact that the Goblin Queen exists to prove that the Sinister might be the worst villain among mutants really says a lot about him.
The Darknet actually has little to do with a man named Nathaniel Essex (now known as "Mr. Sinister"), but his presence looms over X-Men and Notorious The Jean Gray clone in the life of Madeleine Pryor. Sinister's influence on Pryor is evident in Darknet: X-Men #2 - written by Gerry Duggan, with evocative and haunting artwork by Rod Reis. Not since 1989's Inferno has the Goblin Queen and her sinister relationship received such intense attention, dark The Web is an intentional homage. The original Hellfire focused on Pryor's transformation into the Goblin Queen after she and her baby Nathan were abandoned by her then-husband Scott Summers after Jean Gray returned from the dead. Madelyne is then manipulated by the demons N'astirh and Sym. During the event, Mr. Sinister finally revealed Pryor's true history: that she was a clone of Jean Gray, whom Sinister had created for use in a breeding program by pairing her with the powerful Cyclops. Create "Perfect Mutants" and their child Nathan is the result. This was the final straw for Maddie's already fragile sanity. She tries to murder her own children, and "Inferno" ends with Jean Gray absorbing Tracy's memories before Pryor effectively commits suicide.
Madelyne's Waking Nightmare Represents All Of Sinister's Many Victims

While some fans say that making Madelyne Pryor a villain again is a tiresome trope, it's no surprise that even when Magik cedes control of Limbo to Pryor, the traumatized woman will seek to regain her again and again A life thought stolen. The immense pain and trauma that Madeleine still experiences every day is perfectly captured by Reis' expressive art in Darknet: X-Men #2, showing the impact of being all too real Mister Sinister and his attempts at eugenic breeding. Unlike many horrific past mutant villains like Apocalypse, Magneto, and Destiny, who employed truly horrific tactics in an attempt to keep mutants safe and "supremacy," Mister Sinister commits horrific crimes with the sole purpose of gaining more that power. Despite recent news that the original human Nathaniel Essex may have begun researching mutants in an attempt to prevent the destruction of the planet through future technological advancements, it is clear that as he becomes the only supreme being Chances are there that this view quickly disappears. This installment reveals that Madelyne is trying to access the Cerebro drive so she can fully experience the memories of her son Nathan that Jean went through while raising him, a relationship she was forced into by Sinister Sinister and due to his own disgusting Conspiracy stripped away.
Hopefully Darknet's crossover between the X-Men and Spider-Man ends with Madelyne Pryor finally having some kind of real healing from her past wounds, Maybe with the help of Jean Grey and her "stolen" memories. However, her villainy always takes away her agency because A woman and a mother continue to prove that Mister Sinister is the X-Men's worst villain, even if Maddie still needs to be held accountable.
More: X-Men: Magik's Ultimate Sacrifice Backfires on Her