Pokemon Season 4 Episode 163 Episode Title:The Bug Stops Here.Episode Description:Ash meets his rival Casey at the Bug Catching Contest. The competition between the two is fierce. Misty gets mad at Casey because she is pushing her Pokémon too hard. Meanwhile,Team Rocket has trapped Ash in a cage. Casey's Chikorita evolves into a Bayleef to rescue Ash. Ash wins the contest with the prizes: A Sun Stone and a Beedrill Ash had caught. Ash gave the Beedrill to Casey because of her love for striped yellow-colored Pokémon.