The first in a long series of RPGs featuring small creatures who live in elemental-based shells.
Three shelled warriors live on Shell Monster Island, where a demon named Fat Badger was sealed away 1000 years ago.
But he has come back, and is destroying villages in the process.
But, there were supposed to be four shell monsters. Where did the last one go?
And who is this strange person that arrived in Maiyo castle?
Or as Shihtzu says about the back of the cartridge:
"Kaijyu Monogatari  Family Computer
Four heroes set out on a journey to defeat Fat Badger, the resurrected King of Darkness. Build each of their levels by fighting monsters. Find members to add to your party to get new magic at your disposal.
Creating Fun NAMCO"

This game is followed by Big Shell Monsters Story (Daikaijyu Monogatari) 1 and 2 for the Super Famicom,
as well as two dungeon exploration games called Poyon's Dungeon Room for GBC. These games, though, are
closer to a different Birthday game, Dream Master for the Famicom, which is where you have to dig your way
through a labyrinth, hoping to not meet the monsters and traps hidden in the darkness.
Lastly, there were also two cards games for GBC, called Miracle of the Zone. I haven't really checked those out
much. Not too interested in card games.

This was probably my biggest undertaking. This was a big learning experience in ASM. I managed to figure out how to
expand windows, as well as having to recode the text routine. That wasn't fun, but I did manage to add auto word-wrap
to the text, which was almost required to handle the extreme difference in possible line length in battles and shop
dialouge, and the like. I also replaced the mapper-specific save function, with a standard NES method. So, now you
should be able to do normal saves on any emulator supporting mapper 19 (Namcot-106). And you should be able to,
now that I took a few minutes to ensure the text doesn't barf over itself after a save write is finished.

This mission was undertaken by:
KingMike - hacking
shiroi - translation
DvD Translations - ROM expander
Datenshi, Tetsu, others on MO's board - various spot translations