Mammal

Mammals are an almost extinct species in the SS undefined.

It may refer too following characters and species:
 * - Cat - The referee in multiplayer matches.
 * - Cat - The co-referee in multiplayer matches.
 * Mr. Grizz - Grizzly bear - The boss of Grizzco Industries and the main antagonist in Return of the Mammalians.
 * Human - An extinct species that populated the world 12.000 years before the events of the Splatoon series.
 * The Professor - Human - A minor character referenced in the series.

Too a lesser extent, following can be considered a mammal as well:
 * Fuzzy Octarian

The word "mammal" can be found in following modes or missions:
 * , the story mode in Splatoon 3.
 * Return of the Mammalians (mission)