Mighty Cat Masked Niyander (Japanese: ニャニがニャンだー ニャンダーかめん, Hepburn: Nyani ga nyandā Nyandā Kamen) is a 2000 children's superhero anime series produced by Sunrise, loosely based on children's book of the same name by author Takashi Yanase.

It is directed by Tsutomu Shibayama and written by Masaaki Sakurai and Takashi Yanase.

It aired on both Nagoya Broadcasting Network and TV Asahi from February 6, 2000 to September 30, 2001, with a total of 83 episodes (139 segments).

He is kind and truthful at heart and is loved by all, but due to this, he has many rivals.

Nyago/Masked Niyander The main character, but is actually a young cat who is still an elementary school student.

He is a little dull in studies and sports, but as he is caring, cute, kind-hearted, sweet, and understanding, the Cat Wizard chooses him to be Niyander and help the people who are in trouble.

Pidori A brave pterodactyl, and Nyago's closest and most faithful friend.

In case Nyago is far away from his home or hasn't got his bag (where he keeps his Niyander costume), Pidori brings it to him.

He has strong traces of honor and greed in his character, but slowly becomes a popular person in Cat Town due to his variety of attempts to become famous.

But although his self-centered personality is selfishness, he also has a good and friendly nature.

In order to increase Niyon's popularity, she consults Ginko her friend for advice.

Nyanta is an orange cat with stripes, a little plump, loves bellyrubs and he has protruding teeth.

Nyako has pretty green eyes, and is white in color except for a dark grey patch on her head and tail.

Kachin The cleverest cat in Nyago's class, and very patient.

She wears glasses and large white coat and has her own laboratory at a shed beside her house.

Cat wizard He is the one who gave Nyago the mission of to help people in trouble and maintain peace.

HeHe Manto He lives on a mountain at the edge of Niyon woods.

He thinks that he is the king of Cat town, and often challenges Niyander.

His special ability is to create and throw fireballs and lightning from his mouth.

Assisted by his monster minions and skull servants, he attempts to do so several times.

However he manages to undo the curse and started trying to conquer the power of the four magic balls.

He believes in justice and hence helps people in trouble whenever he can, just like Niyander.

To do so he wraps himself in bandages like a mummy to hide his identity, and becomes Miraemaru.

He is in charge of several other TV programs and announces popularity rankings on a daily basis.

She is a bit dramatic at times, and has strong friendship with Pichiko and Kaberina.

He easily becomes ill when he undergoes panic, excitement or temperature change.

Chibikongu A friend of Dekakongu, and is very much like him in appearance, only smaller.

Gaeon He is a strong mountain dog who likes to travel far and wide.

He was suspected to be a criminal at first but later proves that he was not and becomes a good friend of Niyander.