There are unused voice clips for Ryo, Robert, and Yuri that likely relate to the game's climax where Yuri reveals the identity of Mr. Karate.
The in-game announcer mentions the stage name and number while in-between levels. It does this for every stage except for the first one, since the map isn't shown when the single-player starts. However, the game does have a sound clip for the very first stage that is never used.
While the whole cast has visible head damage, King was originally planned to be the only character with chest damage. Some of the animations were seemingly complete before the feature got removed; her famous undressing KO" feature seems to be a leftover from it.
While Ryo and Robert are the only fighters playable in 1-player mode, there are still "time over" animations for the Initiate Super Death Blow bonus stage for each character.
Hidden within the game's data is a chibi portrait drawing of the game's cast. It is unknown if this picture can be displayed during normal gameplay.
Robert's design is based on actors Steven Seagal and Andy Garcia, and the character James Crockett from the Miami Vice series. The character artist, Shinkiro, expressed difficulties in designing Robert on the count of not knowing how rich people behaved.
While most versions of Art of Fighting end on a cliffhanger just before Yuri reveals the true identity of Mr. Karate to Ryo and Robert, the Super Nintendo version extends the ending to reveal that Mr. Karate is Ryo and Yuri's father Takuma, who was blackmailed by Geese Howard and Mr. Big into killing Jeff Bogard (Father of Terry from Fatal Fury)