Entei is a massive lion-like Pokémon with some mastiff qualities. It is covered in brown fur with a long, thick mane covering its neck. It has gray plates surrounding the cape that makes it look as if smoke is coming out of a crater on its back, and a plate beneath the cream belly fur on its chest. Entei has white paws with apparently retractable claws and brown paw pads, and black cuff-like bands on its legs. It has a red face with a white plate that resembles a handlebar mustache on its face, and a three-pointed yellow crest on its forehead. Entei's head appears to resemble a kabuto, a samurai helmet.
It is said that an Entei is born whenever a new volcano appears. It is also said that whenever Entei roars, a volcano erupts somewhere in the world.
Entei is a genderless species.
Entei can shoot flames that are hotter than volcanic magma. It also sports limited mental powers. When it roars, it can make a volcano erupt on another part of the globe.
Entei races headlong around the land.
As a member of the legendary beast trio, Entei are constantly on the move with no set place to settle in.
This Pokémon was unavailable prior to Generation I.