During Comic-Con International in San Diego, we learned a whole lot more about "Guardians of the Galaxy Vol. 2," up to and including the identity of Star-Lord's father and Elizabeth Debicki's role. Additionally, director James Gunn confirmed that "Rocky" legend Sylvester Stallone would be in the film.

"Yes, Sylvester Stallone is in the film," Gunn wrote on Facebook after the panel. "This was an amazing experience for me, considering I ran around in my backyard as a kid pretending I was Johnny Rambo. Working with Sly was one of the high points of shooting 'Vol. 2' for me."

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As to Stallone's character? Well, that's still a mystery. "Who does he play? Well, I can't reveal that quite yet," Gunn teased, "but we do see him interacting with Yondu in the teaser."

Stallone's interaction with Yondu (Michael Rooker) is a vague clue, but it could potentially point to Stallone being a Ravanger, or perhaps even a member of the Nova Corps (if Yondu gets caught in a spot of trouble with The Law, of course). However, it's all speculation at this point.

Directed by James Gunn and starring Chris Pratt, Zoe Saldana and Dave Bautista, "Guardians of the Galaxy Vol. 2" opens on May 5, 2017.