Writer and director James Gunn had the ease of mind knowing that he’d have a chance to make Guardians of the Galaxy 2 for Marvel Studios before the first even hit theaters. He was able to announce it with star Chris Pratt at Comic-Con International last summer and actually began writing the sequel the day the first came out.

As one of the more open and interactive filmmakers in the comic book movie business, Gunn isn’t shy about teasing or confirming certain details about his work with fans on social media or with the press in interviews. Even though GOTG 2 won’t be in theaters until 2017, we’ve already learned quite a few details, especially when it comes to characters.

We know, for instance, that the second Guardians of the Galaxy will see the entire core cast of five “heroes” return alongside Nebula (Karen Gillan), The Collector (Benicio Del Toro), Yondu (Michael Rooker) and his right-hand man, Kraglin (Sean Gunn). We can expect Thanos (Josh Brolin) to make an appearance as well alongside a few other familiar faces.

We also know that Ronan the Accuser (Lee Pace) who seemingly died at the end of Gunn’s first Marvel film may not be dead after all, but he definitely won’t be in the sequel. As for new characters, that’s where things get interesting. The biggest we know about so far is Peter Quill a.k.a. Star-Lord’s dad – a character who Gunn confirmed will be different than in Marvel Comics but who will be very important to Quill’s story going forward.

We also know from what Gunn told us while promoting Guardians of the Galaxy that the main team will include at least two female characters this time around. We can assume both Star-Lord’s dad and this new female member of Star-Lord’s crew are characters from Marvel Comics, even if they’re different, and it’s possible one of them might be James Gunn’s personal favorite character – That or this tweet from the weekend where James Gunn held a Twitter Q&A is hinting at another character about to be introduced into the Marvel Cinematic Universe:

“@MarioMurgueitio: James, is there a favorite superhero you want to bring to the big screen?!!” And will do so in GotG2!

From Gunn’s words, it sounds like whoever this character is, their first introduction will be in Guardians of the Galaxy 2. As for the who of it, looking back on what Gunn has said about projects he’d like to make for Marvel we can make a few guesses.

We know for instance the project he initially wanted to make for Marvel was Hit Monkey. He spoke about that at length when chatting with us on the set of Guardians of the Galaxy in 2012 (he actually wasn’t interested in Guardians at first). The other Marvel fave for Gunn is the villain team-up series Thunderbolts, a project which Marvel Studios boss Kevin Feige teased that Gunn could make if he’s successful with GOTG. We asked Gunn about Thunderbolts too but he said he’s now interested in sticking with the Guardians for a while.

Another Marvel Comic James Gunn frequently namedrops is ROM: Spaceknight, and this one’s quite unique. ROM wasn’t created by Marvel Comics and instead was licensed from Parker Brothers who had acquired the character from its original creators. Marvel ran a ROM: Spaceknight series for 75 issues over an eight-year span until the rights reverted back in 1986.

“@TweetTinyTim: which Marvel character do you wish you could reclaim the rights to so they could appear in your films?” ROM Spaceknight!

— James Gunn (@JamesGunn) March 1, 2015
Since then, Marvel Comics hasn’t been able to use the character but had built so much lore around him that they still can use. Feige spoke briefly about ROM to ScreenCrush last year following a question about the potential of using the character in Marvel movies.

“I think we have Spaceknights, but we don’t have Rom. I think they did some standalone Spaceknights comics at some point. ROM, I believe, was a licensed deal. Like G.I. Joe and Transformers back in the day.”

That’s important to remember because the Galadorian Spaceknights (cyborgs created on Galador to protect the planet from their archenemies, the Dire Wraiths) had a major role to play in the more recent Marvel cosmic stories, specifically during the Dan Abnett and Andy Lanning years where they re-introduced the Guardians of the Galaxy (for which the movie was based on). Their run actually ended with Star-Lord helping start a new team called of cosmic heroes called the Annihilators who would replace the Guardians of the Galaxy after their final, devastating mission to save the universe. There was a Spaceknight on that team named Ikon and their first mission was to save Galador.

“I almost made it work. The Guardians were more than I could ever have hoped for! But the universe is also more dangerous than I ever imagined! Look around! This is the kind of thing that can happen!

The galaxy doesn’t need Guardians! It doesn’t need brave souls! If it’s going to survive another one of these, it’s going to need absolute bad-asses! It’s going to need the biggest guns of all! Cosmic heavy hitters as scary as the menaces they have to face!

It’s going to need flarking annihilators!” –Peter Quill

ROM however, despite rights issues, did make a cameo appearance in 2013′s Age of Ultron crossover event in Marvel Comics and the year prior, Hasbro licensed the rights to sell new ROM toys. Whether or not Marvel Studios has since acquired the film rights or made a deal to use ROM in the movies, it won’t be publicly announced if said character actually will show up in the Marvel Cinematic Universe, but knowing Marvel at least owns the Spaceknights and their homeworld and enemies, etc., makes it possible that they could show up – or at least be referenced – in Guardians of the Galaxy sequels/spinoffs.

Sadly, we’re not counting on ROM the Spaceknight making an appearance though.

Before we start listing some possibilities based on pure speculation, we can at least remove a few possibilities from what Gunn has said in the past.

Carol Danvers, previously known as Ms. Marvel and who now carries the Captain Marvel title, is getting her own solo movie on Phase 3 of the Marvel Cinematic Universe but she will not appear in Guardians of the Galaxy 2. Gunn made it clear that he doesn’t want other Earth characters to take away from that unique aspect of Peter Quill.

Another character Gunn spoke with us about in the past is Bug, a member of the 2008-2010 GOTG team from the comics, but like Rom, he’s also not owned by Marvel. Gunn told us he wanted to use Bug in the first movie but simply could not.

Nova – Similar to Danvers, Nova (both the original Richard Rider version and the new Sam Alexander version) is also Earth-based. Given how Nova Corps was introduced and handled in the Guardians of the Galaxy movie, we’re not even sure the comic book version of this organization (where Nova Centurions can fly and have super powers) will be adapted to the Marvel Cinematic Universe. James Gunn also flat out said that doesn’t want to use Nova “right now...