Looking into the coding of Super Mario RPG: Legend of the Seven Stars reveals several unused enemies (most of which seem to be unused sub-species), including a notorious one known as the Drill Bit. In fact, Drill Bit appears in the game, but does not fight in any battle like a normal enemy.
Material from an early Nintendo Power shows that the Chancellor was once designed differently, being a more elderly-looking, gray-spotted Toad with a beard. It also showed that at least one Buzzer would be in Mushroom Way, and that Frogfucius’s island at Tadpole Pond would be closer and therefore accessed differently. A fishin’ variety of Lakitu would be a helper in Booster’s Tower, which possessed Magikoopa door guards. (It is notable that no fightable Magikoopas other than the red one thought to be Kamek would appear in the final game.) Mario would also encounter Bowser at an unknown time in Bowser’s Keep, and would be pitted against two Shy Aways during this scene. Other material shows that Booster’s Tower would also feature Boos, Dry Bones, and less organized pictures.Nimbus Castle would have a longer walkway and more plants.
A beta version of Super Mario RPG was also seen at a 1995 V-Jump Festival, which also focused on the game’s programming and therefore showed off several features and various other things not meant to be accessible by normal players even by the game’s release.
The presentation of this beta showed that Nimbus Land (which was seen in entirety, even including the Nintendo Power beta Nimbus Castle, at the presentation’s opening) would have differently styled doorways, being simple open holes labeled with a word seeming to be “HOLLOW” or “HOLLOH” rather than the curtains seen in the final version. The V-Jump presentation also featured an animation of a normal, blue-colored Magikoopa attacking and showed Mario running through Mushroom Way (or perhaps Bandit’s Way, as a K-9 was visible) and being chased by several Buzzers, indicating that they would indeed be found en masse in that area in the beta Super Mario RPG: Legend of the Seven Stars.
The presentation also briefly showed a beta Yo’ster Isle, which was much larger and oddly seemed to feature no racetrack. The beta version seen in the presentation also gave Moleville a cloud-filled foreground and removed the blue static seen in the Factory’s foreground. The majority of Nimbus Castle’s interior seen in this beta would appear to simply be more green than that of the final version, although the room where Dodo cleaned Valentina’s statues was depicted as different shades of pink (or perhaps red with pink walls), looking nothing like it did in the final version. This room was also completely flipped horizontally for the final version.
Melody Bay’s composition area also seemed to be longer, and Mario’s Pad was depicted as much larger, and Mario’s house itself even changed in appearance– Much like it was in the final version of Super Mario RPG’s intro, the V-Jump beta depicted Mario’s in-game house as being labeled “Pipe House”. A Treasure Box was also seen in the beta Mario’s Pad; upon being hit by Mario, this box produced a green, 1-Up Mushroom-like mushroom that in itself was not present in the final game. A pair of Terrapins were also seen guarding an exit from Mario’s Pad in this beta.
Lastly, the beta even featured three unused battlegrounds, one of which was a dark, musty castle similar in appearance to Belome Temple, A underwater Battle Stage (which appeared to be from in the Sea Area), the other being a star-labeled circle that may have been a simple testing area.Source
Two unused cutscenes regarding a distressed Princess Peach on the balcony of Booster’s Tower were left in the game’s coding, but did not make the final cut. Interestingly, both were very similar to (but longer than) scenes in the final game.
A translation of the original V-Jump 1995 presentation of Super Mario RPG can be found at Glitter Berri’s website!
Finally, Luigi was believed to be in, as he appeared in a screenshot.