Despite a lot of uncertainty, Phase 1 of the MCU proved to be a success and helped convince Marvel that this massive undertaking was actually working. With its second phase of films, the MCU explored some of its biggest characters while also taking chances on some newcomers as well.

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While the MCU could have continued to make a lot of money by playing it safe, they decided that taking some risks would be more fun. By hiring new filmmakers, departing from the comics, and exploring new sides of the universe, MCU's Phase 2 was an exciting step forward that helped expand the growing franchise. But when it came to the critics, some of the Phase 2 films fared better than others. Here are the MCU's Phase 2 films ranked according to Rotten Tomatoes.

Thor: The Dark World (67%)

Loki looks at Thor and smiles

After seeing Thor primarily on Earth in Thor and The Avengers, Thor: The Dark World took most of the action back to Asgard and further explored the Nine Realms. As Thor tries to bring peace to the Nine Realms, he is reunited with Jane Foster (Natalie Portman) and must stop the Dark Elves who seek to find an ancient weapon known as the Aether.

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While the MCU seemed to be getting more confident with their films, they still seemed unsure what to do with Thor. That lack of confidence showed with a sequel many critics called lackluster. While the cast was still a hit and the humor was welcomed, they found a lot wrong with Thor: The Dark World. From the messy story to the uninteresting love story to the forgettable villain, this sequel hinted at Thor's untapped potential. It remains one of the MCU's lowest rated movies.

Avengers: Age of Ultron (75%)

The Avengers all leap into action in Age of Ultron

After the massive success of the Avengers' first team-up, fans were eager to see them reunite. Joss Whedon returned for this sequel which found the heroes facing off against the evil robotic creation Ultron, who seeks to rid the world of the Avengers. It also introduced new members such as Scarlet Witch, Quicksilver, and Vision to the roster.

Whedon has gone on record as saying the sequel was a particularly difficult production, with some behind-the-scenes drama and that does show in the final cut. Critics were annoyed by the unnecessary set-up for the future of the MCU and also noted that Whedon might have overstuffed the story. The humor was highlighted as mostly a positive but some of it felt too "quippy." But with some great action sequences and surprises, the movie was a worthy if slightly disappointing sequel.

Iron Man 3 (79%)

Seeing as Iron Man was the first hero to get his franchise in the MCU, it makes sense that he is the first one to close out his trilogy as well. Iron Man 3 finds Tony Stark dealing with the aftermath of the attack on New York while being confronted with a new villain in the form of the mysterious and dangerous Mandarin. With no armor to back him up, Stark must rely on his intelligence to back him up.

For this third film, Jon Favreau vacated the director's chair and action movie veteran Shane Black took the helm. Critics didn't seem to mind the change in leadership as they praised Black's distinct voice finding its way into the sequel. The overall storyline was deemed messy by many and the character motivations were somewhat wonky. However, the action, the twists and Robert Downey Jr.'s continued charisma made it a fun ride for most critics.

Ant-Man (83%)

In the comics, Ant-Man is one of the original founding members of the Avengers and was meant to be one of the first movies released in the MCU. Edgar Wright was announced to be spearheading the film and teased it for years before pulling out due to creative differences. Peyton Reed took over with Paul Rudd in the lead role as a thief who becomes a hero to help stop dangerous technology from falling into the wrong hands.

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Though many critics lamented Wright's version being lost, they admitted the version we got was a lot of fun. Though some complained about another weak MCU villain and too much exposition, the comedic tone was a real delight. Rudd made for a lovable hero and the heist element gave the film real energy.

Captain America: The Winter Soldier (90%)

Winter Soldier holding Cap's shield while fighting on the street in Captain America: The Winter Soldier.

Following the events of Captain America: The First Avenger, Cap was brought into the present day which raised a lot of questions about how the character would fit into a contemporary setting. The film wisely embraced the idea of a man out of time and how patriotism has changed since Cap's glory days. The movie follows Steve Rogers as he comes to terms with a world where enemies are harder to spot while also dealing with a figure from his past.

The sequel's new direction was overseen by television directors Joe and Anthony Russo, who would become major players in the MCU. The conspiracy-thriller feel of the movie was praised by critics, as were the new grounded and brutal action scenes. Chris Evans was dynamic in the lead role and the massive plot twists felt appropriately shocking.

Guardians of the Galaxy (91%)

This seems to be the moment where everyone became convinced that the MCU could not lose. The Guardians of the Galaxy were a little-known team from the comics that included a talking raccoon and a tree. On top of that, the film would be responsible for introducing the cosmic side of the MCU. James Gunn was hired to write and direct this space opera which followed a group of unlikely allies who come together to stop an extremist from taking control of an Infinity Stone.

As weird as the film sounded, critics fell in love with it. The cast was praised for the lovable and hilarious performances and the creature designs were applauded as well. Gunn's irreverent humor gave the film a lot of its personality and made this a unique adventure that became a strange and welcome addition to the MCU.

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