Marvel gave fans a lot to be excited about at their Comic Con panel – including surprise appearances from Chris Evans, Scarlett Johansson, Chris Pratt and Zoe Saldana (to name a few), and a big scoop that The Avengers sequel will officially be titled Avengers: Age of Ultron.

Marvel certainly put on a show for their fans, first whipping out a dramatic appearance by Loki – uh, I mean Tom Hiddleston – in full costume to introduce an extended trailer for Thor: The Dark World. Hiddleston performed a short monologue in character, causing fans to erupt in cheers and chant ‘Loki’ as if their lives depended on it.

After the exclusive footage from Thor, the surprises did not stop for a second, as Evans, Johansson, Anthony Mackie and Sebastian Stan from Captain America: The Winter Soldier came out onstage next. The stars answered questions, and revealed that Johansson’s Black Widow is not just making a cameo appearance in the sequel, she is, indeed, working with Captain America for a good portion of the film.

“We get to see how she is in a more casual working relationship. It starts to break down the barriers of the walls she had put up. The film is gritty and has some down and dirty bare-knuckle fighting,” Johansson told the crowd about Black Widow’s role in the film.

Fans were also treated to an exclusive clip featuring Captain America getting in a big fight with suspect characters in an elevator – one of which is Crossbones (a new villain) played by Frank Grillo. The clip also teased Robert Redford’s role in Captain America: The Winter Soldier as Alexander Pierce and, of course, Sebastian Stan as the Winter Soldier.

Next up came a surprise visit from the cast of the upcoming Guardians of the Galaxy. The Pratt-staring movie just started filming, and still, cast members including Pratt, Saldana, and David Batista, Benicio del Toro, Michael Rooker, Lee Pace, and Djimon Hounsou, flew out to San Diego for the Comic Con event. The cast spoke about the casting process, revealing tidbits about their character backgrounds.

“I’ve done blue, I figured why not try green?” Saldana asked the crowd, making a reference to her famed turn as a Na'vi in Avatar.

Even with the film in the early stages of production, the studio put together a short teaser featuring John C. Reilly giving the audience an introduction to the characters.

“They call themselves the Guardians of the Galaxy,” says Reilly at the end of the clip.

Closing out the super star/superhero packed panel was Joss Whedon, who appeared to announce the title of the Avengers sequel, The Avengers: Age of Ultron. In the Marvel universe, Ultron is known as the robot created by Dr. Henry Pym (Ant-Man) – could the title mean that Ant-Man will make an appearance in the next Avengers film? Whedon refused to speculate, but he did treat the crowd to teaser footage.

The Avengers: Age of Ultron has yet to begin production, so the footage relied heavily on special effects and dialogue from previous Marvel films. In the clip, Iron Man’s mask slowly became Ultron. Fans will also note that Age of Ultron is the title of a series published this year, which placed Ultron as a villain who plots to take over the world.

Unfortunately, The Avengers: Age of Ultron isn’t scheduled for release until May 1, 2015. However, Marvel fans will get their superhero fix soon enough when Thor: The Dark World comes out November 8, 2013, followed by Captain America: The Winter Soldier on April 4, 2014, and Guardians of the Galaxy aiming for an August 2014 premiere.

Olivia Truffaut-Wong