While it's confirmed all the major surviving players from the first two Guardians of the Galaxy are returning for the trilogy finisher (along with last week's casting of Adam Warlock), it turns out there are far more roles that have been cast of significance. This comes directly from a comment that director/writer James Gunn himself made in response to a fan's Twitter post today. Check it out below:
Guardians of the Galaxy Vol. 2 ended up having Sylvester Stallone, Michelle Yeoh, Ving Rhames, Smallville's Michael Rosenbaum, and many more show up for bit parts. In addition, Elizabeth Debicki appeared as the High Priestess of the Sovereign people, Ayesha (expected to return in the third film as she was creating Adam Warlock in an end credits scene in that film). Plus, following the events of his character in Avengers: Endgame, Chris Hemsworth is set to appear as Thor (as the Guardians are set to appear in Thor: Love and Thunder as well). Assuming GOTG3 is looking to exceed the first two in scope and given the story revolves around a team that travels throughout the galaxy to protect it, it's a strong bet Gunn is going to take full advantage of his potentially final MCU film in every way possible.
Guardians of the Galaxy Vol. 3 is set to hit theaters May 5th, 2023