Other mistake: At the end of the intro, before the logo appears you can see Mojo Jojo's brain. His brain is green and it should be pink.
The Powerpuff Girls Best Rainy Day Adventure Ever / Just Desserts - S2-E10
Continuity mistake: When Marianne calls Harold to the table, the plant in the middle disappears as they climb on top of it.
Narrator: Sugar. Spice. And everything nice. These were the ingredients chosen to create the perfect little girls. But Professor Utonium accidentally added an extra ingredient to the concoction... Chemical X. Thus the Powerpuff Girls were born. Using their ultra-superpowers, Blossom, Bubbles, and Buttercup have dedicated their lives to fighting crime and the forces of evil.
Boogie Frights / Abracadaver - S1-E5
Trivia: The scene of the Powerpuffs flying along the disco ball is parodied of a scene of Star Wars (episode IV). Note the PPGs having to shoot one area to explode the ball.
Major Competition / Mr. Mojo's Rising - S1-E7
Question: Exactly what did Major man say on TV that caused the PowerPuff girls to get suspicious of him?
Answer: The Mayor says he could never get to the crime scene fast enough and Major Man says "of course not, you'd have to know about the crime in advance, like I do." Major Man let it slip he knew when the crimes were going to happen (because he was setting them up).
Bishop73