Rumors have abound for months leading up to Marvel's Phase 4 opening that Mephisto was going to be the main antagonist in the 9-part WandaVision horror show that is set up to be Vision's swan song, and a likely continuation of Wanda's trauma and ongoing story as it pertains to the future of the MCU. There is little doubt that the ending of this show will provide a sharp contrast to the heart-warming, and innocent tropes of the 50's and 60's sitcom that provided the backdrop to the early episodes. This fun and nostalgic trip down memory lane will only serve to make the ending more difficult for us viewers as Marvel takes us to what so far appears to be, a painful conclusion for our beloved Scarlet Witch.
The first two episodes were ripe with hints that the 'Lord of the Underworld' holds sway over the constructed world of Westview and the fairy tale life of arguably, Marvel's most interesting couple. It has also been well attested to by Kevin Feige that that the story of WandaVision will be woven into both the Spider-Man 3 picture slated for December of 2021 and the Doctor Strange in the Multiverse of Madness project the following year, in profound ways. The idea that Mephisto will be the antagonist in these storylines is buoyed by the fact that the character of Mephisto has as many connections to these heroes in the comics as Visions neural synapses. Further, in comic lore it's perhaps ironic that Mephisto once offered to erase the memory of Peter Parker from the entire world in exchange for ending his marriage to Mary Jane, simply for his pleasure. Did we not leave the famous web-slinger in just such a predicament at the end of Spider Man Far from Home? With that level of power, how easy would it be to erase the memory of 3,892 residents in a small town in New Jersey? It goes without saying!
You can even find a Mephisto easter-egg captured below in the original Avenger's movie in a now edited scene when Nick Fury hands the Tesseract project folder to Steve Rogers. This scene explains that Shield had been working with Mephisto on the Tesseract project prior to The Avengers.
Throughout his comic history, Mephisto often enlisted the help of lesser beings to assist him in his nefarious deeds and the truth is, Mephisto, and quite literally, his 'minions' are right in front of us.
Enter Nicholas Scratch the son of Agatha Harkness in the comic world and who also exercises skilled sorcery to include mesmerism, illusion projecting and soul possession. The overwhelming consensus is that Nicholas' mother, Agatha, is clearly present here in the form of Wanda's pesky and overly exuberant neighbor, Agnes. In the comics, Agatha was often on the side of good and helped Wanda learn to expand and control her powers and later figured prominently in further Marvel narratives as she served as nanny to non-other than Franklin Richards, son of Reed Richards of the Fantastic Four. However, her son was nothing like his mother.
In the comics, Nicholas Scratch was a very capable and dangerous sorcerer and was often an antagonist to his mother Agatha, and her ideals.
Nicholas Scratch first appeared in Fantastic Four #185 in 1977. He hated humans and as the MCU equivalent to Voldemort, believed witches to be superior to human beings. He sought to subjugate humans and their protectors though his leadership of New Salem that he inherited from his mother Agatha after she left to live in the mortal world.
To consolidate his power, he went as far as to transform his own children into the Salem Seven who exercised their new powers to defend New Salem and enact Scratch's plans to kill his own mother, destroy the Fantastic Four and eliminate further opposition to his plans of conquest.
But where is he? We're given a brief glimpse of Nicholas Scratch in episode 2 when Agnes introduces Wanda to her pet rabbit, Senior Scratchy? The reference is obvious here. Although some have postulated that this may be a reference to the name of the devil, popularized by the great short story by Washington Irving, in the Devil and Tom Walker, where the devil is given the nickname 'Old Scratch'. Despite this vague reference, the evidence best serves us that Mephisto's presence lays elsewhere in our narrative and Agnes is keeping her child and ally, close to her.
As mother and son form the family unit here, how can we further establish Nicholas' presence beyond the obvious presence of his mother although that is compelling in and of itself. The best answer to that is by asking another a question...why Westview? Wouldn't a small and indiscrete place like Westview not make the perfect backdrop for a town populated by a coven of witches such as New Salem? This may also explain why many of the inhabitants of Westview have repeated moments of lucidity. Whoever is controlling this temporary reality, may have difficulty maintaining the mind-warping illusions displayed on so many people for so long who may also have magical skills and abilities within themselves.
"After all, what chance would any mortal being stand against a city ruled by...Witches!" - Nicholas Scratch
Agatha Harkness is strongly entrenched within the plot of WandaVision and there is little doubt that her son, Nicholas Scratch is also a minion of Mephisto, and that both he and his mother are both colluding with Mephisto to bring about his plan for Wanda and her children. If Agnes' story arc follows that of the comics, she will become a protagonist and come to Wanda's aid which will alienate her from her son, Nicholas, and the demon Mephisto, as well as provide the complexity of interpersonal dynamics necessary to move the story forward in future movies. This also gives Marvel the option to include Nicholas Scratch in future franchises such as the rumored 'Sons of Midnight' project. If we know anything about Marvel, they think ahead.
Of course, the whole thing may just be a Nightmare. In closing let remind everybody, a rabbit is never just a rabbit in a Marvel movie. Nuff Said!