A shocking new theory suggests that Doctor Doom could prove his salt inAvengers: Doomsdayby killing Tom Holland’s Spider-Man, which could unleash an even greater threat on theMCUafterVenom: The Last Dance. Robert Downey Jr. was confirmed to be coming back to Marvel at 2024’s San Diego Comic-Con, but his recast as iconic Marvel villain Doctor Doom has raised questions for the MCU. While this choice has been controversial,Robert Downey Jr.’s appearance as Doctor Doomcreates some exciting opportunities for Marvel Studios at the conclusion of the Multiverse Saga.
Doctor Doom is expected to make his MCU debut inAvengers: Doomsday, and since he’s billed as the primary antagonist of theRusso brothers’DoomsdayandSecret Wars, he’ll need to make a huge impact on the MCU right out the gate.A new MCU theory presents the perfect way that this can happen by pitting Doctor Doom against Peter Parker’s Spider-Man. This would produce a fantastic full-circle moment forRobert Downey Jr. in the MCU, and could also set up a different supervillain for another Phase 6 movie.

Doctor Doom Killing Spider-Man In Avengers: Doomsday Is The Perfect Full-Circle Moment
Bringing Robert Downey Jr. back to the MCU as a formidable new villain means Marvel Studios has the opportunity to play off the connections between Downey Jr.’s former role of Tony Stark’s Iron Man and the MCU’s other heroes. Perhaps the most prominent of these was Iron Man’s bond with Spider-Man.Stark mentored Peter Parker after recruiting him to help fight Team Cap inCivil War, so Stark’s death had a huge impact on Spider-Man.Doctor Doom having Tony Stark’s facewill likely have a similarly-massive effect, and a new theory shared byComicodigymakes this even worse.
The theory suggests that Peter Parker could beEarth-616’s Anchor Being, a concept first heard in 2024’sDeadpool & Wolverine. Wolverine was Earth-10005’s Anchor Being, contributing to that reality’s deterioration following his death inLogan, and Doctor Doom may set out to kill other Anchor Beings in an effort to save his universe from incursions inAvengers: Doomsday. This puts Peter Parker’s Spider-Man in Doctor Doom’s crosshairs, andhaving Robert Downey Jr.’s Doctor Doom kill Tom Holland’s Spider-Man would contribute to one of the MCU’s most intense and emotional moments.

Peter Parker’s Life Is Saved By Venom In Doomsday: MCU Theory Explained
Venom Is Already In The MCU Before Avengers: Doomsday
The Russo brothers have recently suggested that both of Marvel Comics’Secret Warsstorylines from 1984 and 2015 will inspire events inAvengers: DoomsdayandSecret Wars. This has raised hopes that some ofSecret Wars’most iconic moments will be seen in the MCU, including Spider-Man getting his black alien costume, which occurred during the 1984 event.Upon his return to New York, this black costume was revealed to be the Venom Symbiote, allowing one of Spider-Man’s most iconic villains to debut, and this could also take place in the MCU.
In Sony’s Spider-Man Universe, Venom saved Eddie Brock’s life on numerous occasions, andComicodigy’stheory posits that the Symbiote could do the same for Peter Parker after he’s killed by Doctor Doom inAvengers: Doomsday.After Tom Hardy’s excursion into the MCU in 2021’sSpider-Man: No Way Home, a piece of Venom was left behind, and this small piece might have been growing in power and size in the years since.Avengers: Doomsdaycan mark the culmination of this growth, bringingSpider-Man and Venom togetherfor the first time in the MCU.

Venom & Spider-Man Could Create A New Codex In The MCU
Venom: The Last Dance Introduced New Lore For Venom’s MCU Debut
2024’sVenom: The Last Dancemarked the conclusion of theVenomtrilogy in Sony’s Spider-Man Universe, and wrapped up Eddie Brock’s storyline by having him become permanently separated from a seemingly-dead Venom. New lore was introduced that suggested thatVenom and Eddie Brock’s bond created a “Codex” when Venom brought Brock back to life, which is a new MacGuffin that proved very important toThe Last Dance’sstory. This could also become crucial to the MCU if a new version of Venom saves Peter Parker’s life by bonding with him.
Venom 3’s Codex Explained: What It Is And How It’s Different To Marvel Comics
Venom: The Last Dance hinges around something known as a codex - a concept that also crops up in Marvel comics regarding the symbiotes and their lore.
Venom: The Last Dancerevealed that the Codex inside Eddie Brock was necessary to freeKnull, the creator of the Symbiotes, from his imprisonment on Klyntar. Brock’s Codex was seemingly destroyed when Venom left him and sacrificed himself, which currently means there’s no way for Knull to break free. However,a new Codex being created by Venom and Spider-Man bonding inAvengers: Doomsdaywould surely get Knull’s attention, and since he’s a multiversal threat, this turn of events would fit perfectly into the Multiverse Saga.

Avengers: Doomsday Theory Teases Knull As Spider-Man 4’s Primary Villain
Spider-Man 4’s Villain Hasn’t Yet Been Confirmed
Despite being one of Marvel Comics' most terrifying and dangerous recent supervillains, and his live-action debut inVenom: The Last Dancebeing very exciting,Knull’s live-action future hasn’t been confirmedby Sony Pictures or Marvel Studios.Since Sony’s Spider-Man Universe is now over after the disappointing release ofKraven the Hunter, Knull should make the move to the MCU proper, and this debut can be teased by the creation of a new Codex inAvengers: Doomsday. This would set up Knull as a key figure in Marvel’s following movie, 2026’s much-anticipatedSpider-Man 4.
Andy Serkis portrayed Knull inVenom: The Last Dance. Serkis previously appeared as Ulysses Klaue in the MCU’sAvengers: Age of UltronandBlack Panther, and he was also the director of 2021’sVenom: Let There Be Carnagefor Sony.

Destin Daniel Cretton’sSpider-Man 4will catch up with Tom Holland’s Peter Parker after the events ofSpider-Man: No Way HomeandAvengers: Doomsday. Since everyone has forgotten Peter Parker,Spider-Man will need new allies in his Phase 6 sequel, and he’ll be taking on new, currently-unknown villains. If he bonds with Venom inAvengers: Doomsday, both the Symbiote and his creator would make excellent choices for villains inSpider-Man 4, giving more weight to Knull’s SSU debut, and exploring the continued impact of Doctor Doom’s destructive actions in the MCU.


