>Director James Gunn added Ego as Star-Lord's father before learning that the characters rights belonged to 20th Century Fox. The studio eventually traded Ego to Marvel Studios in exchange for Negasonic Teenage Warhead, who appeared in DEADPOOL.
>Gunn was advised against including a particular alien race, the Sneeps, because their name resembles the Icelandic slang for female genitalia. The studio eventually relented to their appearance.
>Early drafts included the Nova Empire. John C. Reilly and Glenn Close were approached to return as Daenerian Rhoman Dey and Nova Prime Irani Rael, but Reilly was unavailable due to scheduling conflicts, and was ultimately written out alongside Rael.
>Early drafts included the Collector, but Benicio Del Toro couldn't return to scheduling conflicts.
>Early drafts featured Adam Warlock as the Sovereigns' secret weapon, but the character was ultimately cut as he was superfluous to the narrative.
>Early cuts featured a longer segment on Earth including cameo appearances from Nathan Fillion as fictional actor Simon Williams and Gregg Henry as Grandpa Quill in a scene filled with Easter Eggs but both were ultimately cut from the movie.
>Early cuts featured a sixth post-credits scene in which Gamora and Mantis hearing the screams of one of the Ravagers who were pierced by Yondu's arrow and has presumably been forgotten and screaming in agony throughout the third act of the movie. This was deleted as test-audiences didn't get the joke.
>Early cuts featured a minor scene of Drax loudly slurping soup to his teammates' annoyance which was cut for time.
>Matthew McConaughey was approached to play Ego, but ultimately declined, and Kurt Russell was cast at Chris Pratt's suggestion. Liam Neeson and Gary Oldman were also considered.
>David Bowie was slated for a cameo before his death in 2016.