As is tradition with Marvel movies and the recent video games, Marvel's Guardians of the Galaxy has a post-credits scene. Typically, these scenes are meant to reward players/viewers for staying through the credits and tease what's to come from the next entry in the series. Marvel's Guardians of the Galaxy sort of does this, but it is not the grand teaser that some fans may be accustomed to from the Marvel universe.
[Warning: Major spoilers for Marvel's Guardians of the Galaxy are below.]
One of the many twists in Marvel's Guardians of the Galaxy is quite layered. Near the start of the game, Star-Lord believes a one-night stand with Ko-Rel over a decade ago resulted in her becoming pregnant with his child known as Nikki. He doesn't know for sure, but to him, the math adds up, and is left with this thought throughout the game. By the end, the spirit of Ko-Rel - who is trapped in the Soul Stone - reveals that Nikki is not Peter Quill or Ko-Rel's biological daughter. Ko-Rel notes that she found Nikki as a baby during the galactic war and essentially took her in.
By the end of the game, the Guardians rescue Nikki from the clutches of Magus and Raker. She ends up being powered by the Soul Stone and helps defeat an evil Adam Warlock in the Guardians game, cementing her as a valuable member of the team. Given she's a child, she has nowhere to go and the Guardians take her in. After the credits, Rick Astley's "Never Gonna Give You Up" fades in as Star-Lord is debating himself in the mirror about whether or not he'll be a good surrogate father and if Nikki will have a good upbringing on the Milano. The player is allowed to choose the mirrored Star-Lord's responses, whether it be in support or opposition.
How Guardians Of The Galaxy Game's Post-Credits Scene Hints At A Sequel
Eventually, Star-Lord is interrupted by Drax who tells Quill that the Guardians voted on Nikki taking his room. Rocket confirms the vote was unanimous and that he'll have to take the couch. Quill doesn't put up much of an argument and then the Milano is seen flying off into the stars, in search of more business cards. Generally speaking, the ending of Marvel's Guardians of the Galaxy doesn't set up the next big threat or any other concrete ideas for where the series could go.
In terms of setting up a sequel, there are some basic seeds with Adam Warlock reclaiming the Soul Stone and Nikki being part of the Guardians. However, there isn't a grand plan or villain in place for a follow-up. Whether or not a sequel to Marvel's Guardians of the Galaxy will happen remains to be seen, but if it does, it could dabble in Quill actually having to serve the role of a father in a child's most formative years.