These are the characters of Cave Story. Please be advised as there may be spoilers here for those who have not yet played through the game.
A robot who was sent to the island 10 years ago in order to destroy the Demon Crown along with the help of Curly Brace. However in this circumstance, he and Curly are stereotyped by some as the same as other killer robots who were previously sent to the island by various world governments in order to retrieve the Demon Crown and destroy anything in their path.
- Sue Sakamoto
The sister of Kazuma and daughter of Momorin Sakamoto who is searching for a means of foiling the doctor's plans of world domination, however along the way she has been turned into a Mimiga by the witch, Misery.
- Kazuma Sakamoto
A scientist heading the research of the Mimiga island and the brother of Sue. He has somehow become trapped in a room on the island with no means of getting out by himself.
- Momorin Sakamoto
Another scientist conducting research on the island and the mother of Sue and Kazuma. Her specialty is the construction of rockets.
- Curly Brace
A specialised combat robot who seems to be suffering from memory loss, all she knows now is that a group of Mimiga children have chosen her as their guardian and she will do whatever is necessary to protect them.
A mysterious blocky-looking henchman in the service of the doctor.
A powerful witch in the service of the doctor. She is the daughter of an even greater witch named Jenka, who watches over the island.
- The Doctor (Date)
He has claimed a mysterious forbidden relic of the island, the Demon Crown, as his own. This crown gives him unimaginable power as well as servants that are bound to the crown bearer. The doctor wants to raise an army to take over the surface by any means necessary.
The newly appointed leader of Mimiga village after Arthur was killed by the doctor and his henchmen. He is stubborn minded at times, but he only wishes for the protection and safety of his fellow Mimiga brethren.
- Professor Booster
A professor of engineering who is related to the Sakamoto family and has accompanied them in order to research the island. His specialty is jet pack engineering.
A good-hearted, but timid engineer who has come to the island with the Sakamoto family to lend a hand in the research. However, after the doctor came to power he was turned into a mimiga by the witch Misery. His specialty is the design of automated rockets.
An innocent little Mimiga who is trying to protect an ostracised Sue from the rest of the Mimiga village. However she has become involved in a dire situation...
The second in command of Mimiga village. He guards the entrance to the town graveyard and protects the village from the monsters that reside there.
An old witch who has lived on the island a very long time, she is the guardian of the island and also over that of her brother, Ballos. She enjoys talking and spending time with her five puppies.
Jenka's brother and an extremely powerful sorcerer, however on the account that he was tortured until he became psychotic and had his powers run wild, he was sealed by Jenka on the island as an eternal sentence.
A Mimiga who ate a red flower, turning him into a monster.
- Killer Robots
Robots that were dispatched to the island 10 years ago by various world governments in order to retrieve the Demon Crown. Programmed to destroy anything in their way, they started a war against the Mimiga until they fought back using red flowers. The 9th team of robots was eventually stopped by something on the island...
- The Korons/Colons
The children Mimiga of Sand Zone that were raised by Curly and are under her protection.
A female Mimiga who lives with her grandfather on the island's plantation.
- Dr Gero
The resident physician of the labyrinth. He recently had to abandon his old clinic on the account of some ghost trouble.
- Squid (Ikachan Cameo)
Appears before Quote after the fight with Ironhead if Quote does not lose health during the fight. Like Ironhead the squids are cameos from another of Pixel's games called Ikachan.
Jenka's pet and leader of the dogs. While searching for his brothers, he got lost and was taken in by Curly.
Jenka's pet. Spends most of her time asleep, but her dreams have been known to portend the future.
Jenka's pet. Loves treasure-hunting. Or treasure *chests*, rather, and recently has taken up sleeping in them.
Jenka's pet. Loves dark places. Due to poor eyesight, he roams the darkness using his wild instincts alone.
Jenka's pet. Adores bones and has buried them in countless places, most of which are by now forgotten.
The legendary Mimiga who fought against a mysterious inner evil of the island and drove it back. However he was eventually killed by the Doctor and his servants.
An aged Mimiga who looks after his grandaughter on the island's plantation.
A stingy Mimiga in charge of managing and repairing sprinklers used on the island's plantation.
- The Shovel Brigade
Worker Mimiga who are being used by the doctor in tending to the red flower crops on the island's plantation.
A Mimiga who loves fishing.
A Mimiga who loves to eat.
A Mimiga that loves to play with fire apparently. He has recently lost the key to his home in Grasstown.
A hermit gunsmith who has been working long hours on perfecting his weapon, the polar star.
Manages the crops at the Yamashita farm.
The coloured Mimiga. She takes pride in looking nice by using various makeup products. She also has a secret passageway in her house through a fireplace.
The security robot that watches over the Power Room of Grasstown. He is good at making explosives.
Manages the labyrinth shop and will help any traveller by giving them something useful.
- Nurse Hasumi
The nursing assistant to Dr Gero.
- The Littles
A family of tiny people who live in a quaint home in the outer walls of the island.
Mysterious natives of the island who know much and oftentimes supply helpful information to travellers.
A statue carver that doesn't have much to say to anyone. He spends his time carving the statues in the likeness of the all of the Demon Crown's previous owners: Halda, Annachponae, Miakid as well as the latest addition, the doctor.
- Ma Pignon
A mysterious mushroom unlike any other living in the graveyard. He is considered valuable to some. He enjoys playing tricks on anyone who has business with him.
Various robots that still wander the island with no purpose or direction other than their original programming.