
Following his fate in Loki Season 2, many had no idea how Tom Hiddleston's Loki would play into Avengers: Doomsday, but now he will reportedly be the glue for the entire premise of the movie.
Avengers: Doomsday is shaping up to be Marvel Studios' biggest film to date. With the return of Robert Downey Jr. in an entirely different role (Doctor Doom) and the inclusion of so many new characters such as the Fantastic Four, many have no idea what to expect the final product to look like.
However, many always expected Hiddleston to be in the film in some capacity, but it seems as though he may be more vital than anyone could have ever imagined.
Loki's Role in Avengers: Doomsday Revealed

Industry insider Alex Perez held a recent Q&A column on The Cosmic Circus to answer questions about future Marvel projects, specifically Avengers: Doomsday.
One fan asked Perez what Loki's role would be in Doomsday and/or Avengers: Secret Wars, and Perez's answer was rather shocking.
According to the insider, Loki will be at the center of the entire story, operating as the "MacGuffin." In films, TV, or literature, a "MacGuffin" is a plot device that moves the plot forward. For example, the One Ring is the MacGuffin of the Lord of the Rings trilogy since that is what motivates the major characters.
Perez went on to tease that "who gets to Loki first" will get the upper hand in the coming movie:
"He’ll be our McGuffin. The race against Doomsday will be a race to see who gets to Loki first."
So, in other words, Loki will not only be featured heavily in Avengers: Doomsday, but will be the device the entire plot relies on.
Why Is Loki So Important in Avengers: Doomsday?
The ending of Loki Season 2 was confusing for some fans, but, in short, it essentially revealed that Loki was the God of Stories. In other words, he became Loki Who Remains, being able to hold power over time and control over the existence of branches throughout the Multiverse.
So, since Doomsday will be exploring the Multiverse further and featuring it in a vital way, Loki will be more than valuable to whoever can reach him.
As Perez explained, he will be the key to the story and all parties will be racing to get to him. Of course, Loki's intentions are never clear and he is one of the most unpredictable characters in the entire franchise, so it will be interesting to see how he responds to characters like Doctor Doom.
Many also have to be wondering what will happen when Loki inevitably comes face to face with someone such as Doom, especially after Thanos killed Loki when they met at the beginning of Avengers: Infinity War.