Ditto's Mysterious Mansion - S1-E36
Audio problem: When Ash tells his friends to help save Ditto, Misty speaks, but her mouth does not move. (00:14:26)
Ditto's Mysterious Mansion - S1-E36
Continuity mistake: When Duplica says that she will be taking her Ditto back from Team Rocket, the white trousers on Brock's disguise turn brown, like the trousers he usually wears. (00:15:53)
Ditto's Mysterious Mansion - S1-E36
Continuity mistake: When Duplica goes over to her wardrobe to change into a Nurse Joy costume, the red brim of her Ash costume turns white. (00:06:02)
Ditto's Mysterious Mansion - S1-E36
Continuity mistake: When Ditto, as a Bulbasaur, uses Vine Whip, it is briefly drawn with nostrils, even though it had not mastered changing its face at this point. (00:05:22)
Ditto's Mysterious Mansion - S1-E36
Continuity mistake: When Ash's Bulbasaur uses Razor Leaf, its nostrils disappear, while the inside of its eyes changes from white to black. (00:05:16)
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.