Butterfree is a lepidopteraninsectPokémon which resembles a vaguely anthropomorphic butterfly with a purple body. Unlike true insects, it only has two body segments and four light blue legs. The upper pair of its legs resemble small, three-fingered hands, while the lower pair resembles long, digit-less feet. Butterfree has two black antennae, a light blue snout with two fangs underneath, and large, red compound eyes. Its two pairs of wings are white with black venation. Two oval scales on a female Butterfree's lower wings are black, but they are white on a male.
The wings of Butterfree are coated with poisonous scales that easily fall off continuously as it flies. If inhaled, it results in several status conditions. It will defend Caterpie from bird Pokémon using this powder. This powder also repels water, enabling it to fly and gather honey even in the rain. Butterfree can use its sensitive antenna to detect the odors of blooming flowers six miles (ten kilometers) from its nest in search of nectar, which it carries with the hairs of its legs. Sometimes, it has territorial disputes with Cutiefly over fields of flowers. It also consumes sap from trees pierced by Heracross, as seen in the anime. Butterfree is found in temperate forests and jungles, but it has also been observed flying near the ocean as part of its migratory breeding pattern.
As Gigantamax Butterfree, its wings become shades of bright and dark green with a white pattern on them. At the base of the wings are a fur-like circle, which attaches to Gigantamax Butterfree's back. Its antennae become bright green as well, and extend to the point where the tip bends, and three red clouds surround them. Its eyes glow bright red. Several green scales, created from crystallized Gigantamax energy, can be seen floating around Gigantamax Butterfree. These are its most effective weapons, capable of causing paralysis, poisoning, or sleep. Gigantamax Butterfree scatters these scales by the winds that it generates with each flap of its wings; these winds are powerful enough to lift a 10-ton truck.
In Bye Bye Butterfree, Ash's Butterfree fell in love with a pink Butterfree and fought to save her from Team Rocket. At the end of the episode, Ash released his Butterfree to mate with the pink Butterfree. The pink Butterfree reappeared in I Choose You!, which is set in a timeline different from the main series.
Multiple wild Butterfree appeared in Bye Bye Butterfree, all under the ownership of Trainers who released them so they could engage in a mating ceremony. Ash's Butterfree became one of these Butterfree.
In Butterfree and Me!, multiple Butterfree evolved from Metapod on Wayfarer Island. One Butterfree had been befriended by Ash as a Caterpie, and Ash spent much of the episode helping it eventually evolve into its final form.
In I Choose You!, multiple Butterfree engaged in a mating ceremony that Ash's Butterfree took a part of, much like the events of Bye Bye Butterfree.
Butterfree was the first Pokémon shown in the anime with an alternate color, pink in its case. This has only been seen in a single female, and unlike a Shiny Butterfree, which has green eyes and pink wings, limbs, and snout, this Butterfree only differed in its pink body and wings.
Butterfree shares its category with Beautifly. They are both known as the Butterfly Pokémon.
Butterfree can be seen as a parallel to Beedrill. Both of their unevolved stages evolve at level 7 and again at level 10. They both go through metamorphosis-like evolution and have the same base stat total of 395. Also, while Beedrill is exclusive to Black and Black 2, Butterfree is exclusive to White and White 2. Both also have an alternate form only available in-battle (Gigantamax Butterfree and Mega Beedrill, respectively).