Kaijuu Monogatari ("Shell Creature Story") is an 8-bit RPG for the NES that more than superficially resembles Enix's Dragon Quest. As with many RPG contemporaries for the system, it borrows the basic premise (talk to the King, discover what to do next, fight some evil force) and the turn-based tactical combat and gradual character development of its major influence, but also much of its aesthetic: The box art has some Akira Toriyama-inspired artwork and the protagonist wears a familiar suit of blue armor. Kaijuu Monogatari's subtitle - Shell Saurs Story - is a localization of its Japanese name.
The plot, in greater detail, concerns a race of peaceful shell creatures that have four elemental warriors that united to fight the villainous Fat Badger but were separated in the final struggle. The player needs to unite the four by exploring the world and discovering the locations of the other three warriors, then regrouping for another attack.
A unique twist, though one that would also become a feature in Dragon Quest IV (thus coming full circle innovation-wise), is that the player is able to assume any of one these four heroes at any point by selecting a menu option, though each one begins at level 1 and is very weak. In order for the party to be strong enough to meet up, each must be independently raised to a sufficiently high level.
The game would eventually spawn its own franchise with sequels and spin-offs being released for the Super Famicom and Game Boy in Japan.