Located within River City High School's First Floor A, there is a poster that reads "Try Hard", which is an in-game parody of the 1998 film Die Hard. Upon further inspection, there will be a vent hidden behind the poster and upon entering it, the player will be rewarded with the "TV Dinner" achievement, with the description referencing the same line said by John McClane during the air vent scene in the movie.

The "Make Milton Proud" achievement, which requires the player to destroy the computers and walls within the cubicles at Technos, references the 1999 film Office Space, with the title itself poking fun at the character of Milton Waddams, and the achievement's description utilizing the same phrase expressed to Peter Gibbons from the movie.

According to an interview with Siliconera, the shopkeeper who runs "Suzy's" store is based on game director Bannon Rudis's mother in real life.

According to an interview with Siliconera, Bannon Rudis considered adding Chris from River City Ransom: Underground as a playable character at one point during development before deciding on both Marian from Double Dragon and Provie from the former.

When YouTuber Jacob Rabon IV ("Alpharad") provided the voice of the Ferryman, the game's voice director Cristina Vee did not have a picture of the character on hand, simply describing him as "a man on a ferry that gives boat rides." According to Rabon, he imagined him dressed as a "carnie", and thus provided his lines with an upbeat "YouTuber voice". He only learned that the character actually resembled a skeletal monster upon the game's release, and jokingly felt that this ruined his chances at a career in voice acting. Rabon also provided the voice of the dog Shou-kun, opting to verbally say "woof" instead of recording soundbites of him barking as he did not feel comfortable doing that.