With 25 films to its name, Marvel Studios has come a long way since its humble beginnings in 2008. Nowadays, the Marvel Cinematic Universe is a pop culture powerhouse, but it wouldn't have been able to take off in such a major way if the movies of Phase One hadn't set a solid base to build upon. While some of the installments may have been met with a fairly tepid reception, Phase One is regarded fondly overall thanks to its dedication to exploring its characters while also building out the wider universe.

Here is a ranking of the six films in the MCU's Phase One, based on an average of their Rotten Tomatoes and Metacritic scores.

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The Incredible Hulk - 64

For years, The Incredible Hulk has been seen as the odd one out of Phase One, and this is reflected in its low reviews. While Edward Norton's performance as the titular hero was praised, some of the effects were criticized, especially in the CGI-heavy final battle between the Hulk and the Abomination. Despite this, the film was overwhelmingly regarded as a more enjoyable Hulk movie than Ang Lee's 2003 effort. After years of seemingly ignoring this film's events, Marvel has recently begun to incorporate elements from it back into the MCU, such as the return of the Abomination in Shang-Chi and the Legend of the Ten Rings.

Iron Man 2 - 64.5

Iron Man and War Machine facing off in Iron Man 2

Iron Man 2 was Marvel Studios' first sequel, and while it wasn't seen as a failure by any means, critics agreed that the movie wasn't as good as its predecessor. Critic Deborah Ross at The Spectator summed up most of the complaints towards the film when she said, "If there were any new ideas, I failed to spot them." Despite this, Robert Downey Jr.'s performance as Tony Stark once again received near-unanimous praise, as did the replacement of Terrence Howard with Don Cheadle in the role of James Rhodes.

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Thor - 67

Thor, Odin and Loki in 2010's Thor

Kenneth Branagh's Thor introduced the MCU's most powerful superhero (at the time) and balanced the character's more sci-fi elements with a Shakespearean family story. One aspect of the film that was unanimously praised by critics and audiences alike was Tom Hiddleston's Loki. Reactions were more divided on the movie's story and pacing, with Nick Schager of Lessons in Darkness calling it a "merely adequate introductory saga coated in hammy reality."

Captain America: The First Avenger - 73

After Chris Evans' portrayal of Johnny Storm in Tim Story's Fantastic Four films, audiences were uncertain about how to feel when it was announced that he was going to play Captain America in 2011's Captain America: The First Avenger. However, any fears were assuaged after the movie's release, as Evans' portrayal of the Star-Spangled Man received widespread praise. Critics and audiences also applauded the film's supporting cast as well as its 1940s setting but panned its pacing and its seeming reliance on clichés.

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The Avengers - 80

Avengers-2012

By bringing together heroes from across the MCU, The Avengers changed the game for superhero movies forever. While its two-hour-40-minute runtime was criticized, the final installment of Phase One was ultimately celebrated as a success, with Discussing Film's Nicolás Delgadillo calling it "a validation of comic book storytelling as an art form." Particular praise was devoted to the movie's special effects and the performances from its lead actors, and it made Joss Whedon a hot commodity for several years before his eventual fall from grace.

Iron Man - 86.5

Tony Stark standing in his lab in the Iron Man suit in 2008's Iron Man.

Without 2008's Iron Man, there would be no Marvel Cinematic Universe. Jon Favreau captained the ship of the MCU's first installment, but it was Robert Downey Jr.'s performance as the titular hero that led the film to worldwide success. Iron Man instantly shot from a B-list hero to an all-time superstar, and his first movie proved to the world that superhero movies could be successful, paving the way for the epic franchise that followed it.

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