Quilava is a quadrupedal mustelidPokémon with a long, slender body. The top half of its body is a dark blue-green, while its underside is cream-colored. It has triangular ears with dark red interiors, a rounded snout, and triangular red eyes. Each of its paws has three toes. It has five red spots on its body that can project flames: two arranged vertically on its forehead and three lined up horizontally on its rear.
Before a battle, Quilava turns its back so its flames face its opponent. It battles using these intense flames in combination with gusts of superheated air. Its own fur is non-flammable, which protects it from other fire attacks. Quilava tends to be rare in the wild, but can sometimes be found living on grasslands. When exposed to the mysterious energy of Mount Coronet in Hisui, Quilava's evolution is altered, gaining it the Ghost type as it becomes Hisuian Typhlosion.
Quilava shares its category with its evolved form and Entei. They are all known as the Volcano Pokémon.
Coincidentally, they all are capable of learning Eruption.
Quilava, Charmeleon, and their respective evolutionary lines have exactly the same base stats in the same distribution.
Jeff Kalles, who assisted in the naming of many Generation II Pokémon, suggested the English name for Quilava. According to Kalles, he suggested the name because Nintendo and The Pokémon Company wanted a Pokémon for every letter of the alphabet.
Quilava's body is similar to most animals in the weasel family, particularly stoats due to its lack of a tail and the fur on its upper body being significantly darker than that on its underbelly with elements of a badger. However, the pattern distribution and shape of Quilava's flames closely resembles the quills and crest of the crested porcupine, especially in its earlier sprites. It may also be based on volcanoes due to its triangular profile when standing up and the ability to learn Smokescreen and Eruption.
Quilava may be a combination of quill (a needle-like hair) and lava (extrusive molten rock).
Magmarashi may be a combination of magma and 山荒 yama-arashi (porcupine).