August 19 marks the anniversary of one of Pokemons most emotional episodes, Season 1s Bye-Bye Butterfree. Ash Ketchum and his friends went through many memorable adventures and moments throughout the original Pokemon animes first 25 seasons, including a few heart-wrenching farewells to Pokemon that they had previously caught and formed a bond with. The first of these was with Ashs Butterfree, which he originally captured as a Caterpie way back in the shows third episode.