Kyouryuu Ouji Don (lost build of cancelled Super Famicom role-playing game; 1994)
From The Lost Media Wiki
Kyouryuu Ouji Don (also known as Don) is an cancelled 1994 Super Famicom RPG action side-scrolling game that was in development in 1994 by Taito that starred a triceratops named Don who must solve many problems that plague the populace of the cute animals.
Before having a name, Taito run a contest in Japan to name the dino and a game. The game was meant to released in Japan and as well as a US release after that but both releases were cancelled for unknown reasons.
No prototypes or other information of any versions of the game have surfaced.