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Pokemon, I Choose You! - S1-E1
Other mistake: When Pidgey turns its head to see Ash with a Poké Ball, its head feathers beside its eyes are mistakenly coloured cream instead of brown. (00:11:36)
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Pokemon, I Choose You! - S1-E1
Other mistake: When Ash gets Pikachu's Poké Ball from Professor Oak, the latter's hand right hand is drawn backwards. (00:06:52)
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.