Saim Cheeda is a freelance entertainment writer who is regularly featured on mainstreams sites such as Screen Rant and Fansided.
The Marvel Cinematic Universe's "Infinity Saga" concluded with Spider-Man: Far From Home. Among the story arcs the three phases detailed, the top villains of The Avengers films were Loki, Ultron, and Thanos.
While Thanos and Loki did close out their arcs over an extended period, Ultron's story was fairly self-contained, even incomplete to a certain degree. Appearing in the title no less, Age of Ultron left out plot lines that weren't given time to be expanded upon. The most striking of these was his hatred for Tony Stark, the man who created him in the MCU.
In the comics, Ultron faced a similar contempt for Hank Pym, who is credited as his creator in The Avengers #58. This hatred stemmed from his inability to understand why he was created, and the lack of choice he had for being passed on Pym's brain patterns.
The MCU Ultron despised Stark for the same reasons, calling him "a sickness" and slicing off Ulysses Klaue's arm for suggesting he was part of Stark's Iron Legion. Ultimately, Ultron's attempts at patricide were both thwarted and downplayed by the film's climax.
Tony Stark did have another "creation" of sorts later on with Spider-Man. Peter Parker certainly saw Stark as his mentor, and with no Uncle Ben yet in the MCU, Stark was essentially there to fulfill the father figure role. Unlike Ultron, Tony was there for Peter, helping him both with controlling his powers and providing emotional support.
The knowledge of this relationship is what motivates Ultron to place his feelings of vengeance toward Spider-Man by considering Peter Parker to be his "brother."
As for his resurrection, It was explained in Age of Ultron that he'd been eradicated from the internet and Vision destroyed the last Ultron Sentry. However, considering Arnim Zola's return in Captain America: The Winter Soldier by becoming an A.I., it's not out of the realm of possibility that a fragment of Ultron might have survived as well.
Ultron, disguised as The Crimson Cowl, had demonstrated powers of hypnosis by using it against Edwin Jarvis in Avengers #54. The climactic scene of Peter's identity being exposed as Spider-Man in Far From Home can be the result of a hypnosis placed on him by Ultron under this theory.
Ultron's endgame would be to eradicate any remaining members of the Stark family, thereby forcing Peter to protect Tony's daughter Morgan. The MCU's Spider-Man films have used Tony Stark as a backdrop for the plot - and what better way to provide closure to this quasi-family arc than by pitting both "Sons of Stark" against one another.
© 2020 Saim Cheeda