The Real Reason Ultron Is The Ultimate Villain In What If...?

Contains spoilers for the season finale of "What If...?"

Marvel's "What If...?" series gave fans one of the biggest baddies in MCU history: Infinity Ultron. After taking out Thanos with a single blow, the unhinged A.I. system serves as the main antagonist for the last few episodes of "What If...?," and is one of the highlights of the entire series. 

Actor Ross Marquand, best known for playing Aaron on "The Walking Dead," voices Infinity Ultron and ultimately takes the place of James Spader, who played the genocidal A.I. in "Avengers: Age of Ultron." The 2015 film was the first and only time that Ultron has been featured in the MCU, but the character has been a mainstay in Marvel comics since first being introduced in the late 1960s. 

Now that "What If...?" has ended, head writer AC Bradley and director Bryan Andrews have started opening up about what went into choosing Ultron has their big bad in Season 1. They spoke to Entertainment Weekly recently about the specifics.

As comic book fans know, Ultron's place in the Marvel universe is one that deserves much more than just one movie — and the "What If...?" creators recognized this. 

"Ultron is a huge character in the comics and while Age of Ultron was a lot of fun, he just got one movie where Thanos gets a whole series," said head writer AC Bradley, speaking to EW. "So we wanted to give him his due and show the actual pure terror of this horrific A.I. that was created from a place of altruism and arrogance and see what he would actually do if unleashed. And because we now have the Infinity Stones and the multiverse to play with, it gets more and more horrific. And we got to show the human side of that tragedy and focus using both Clint and Natasha and their relationship. I love those two characters so getting to see them up close and personal, and how they interact with each other was a blast to write and work with."

Director Bryan Andrews told EW that having Infinity Ultron play a major role in "What If...?" was one of the first things the creative team got behind. "Way, way early on, even before we started breaking story and figuring out what was even going to be in the first season, the notion of having something where possibly Ultron won in some capacity was always kicking around," he said.

Judging by the fan response to the final episode, it's a decision that definitely paid off.