Showdown at Dark City - S1-E40
Revealing mistake: When Ash apologises to the young boys, one of the boys' left arm is disconnected from his body. (00:02:09)
Showdown at Dark City - S1-E40
Continuity mistake: When Kaz sends out his Electabuzz during the final fight, the red "K" on his shirt turns blue like the rest of the shirt. (00:12:40)
Showdown at Dark City - S1-E40
Revealing mistake: When the Yas Gym underlings send out their Pokémon to attack Ash, the Poké Balls disappear into thin air. (00:09:51)
Showdown at Dark City - S1-E40
Continuity mistake: When Yas first tells his Scyther to attack, the clips on his uniform disappear. (00:04:03)
Answer: He is a good guy but just found himself in a bad situation when he worked for Lysander. He didn't want him to harm Ash and his Pokémon when he was trying to get the special bond between Ash and his Greninja to work. He does leave Lysander and go back to being a good person.