Pink Butterfree

As the very first instance of an alternate-colored Pokémon featured in the anime, this unique Butterfree holds a special place in series history. Appearing even before shiny variants were officially introduced in the video games, its distinct rosy hue was likely used by animators to help viewers distinguish it from the standard Butterfree species during its specific episode. This rare creature serves as a fascinating early example of how the show experimented with unique character designs.