Factual error: When Luke is playing video games in the camp he is using a Playstation controller, however when he pauses the game it shows a message telling him to push the 'B' button. 'B' buttons appear on Xbox games consoles rather than Playstations.
Factual error: The Athena Parthenos is a bad copy, she should hold a smaller statue of Nikè in her right hand, but she holds her spear.
Plot hole: In Aunty Em's Emporium, when Medusa turns the older woman to stone, she has hold of Annabeth's wrist and Annabeth cannot free herself. Grover comes along later, as Percy is keeping Medusa busy, and breaks the arm of the statue that is holding Annabeth (near the elbow). Annabeth is able to easily pry the statue's severed arm's grip from her wrist, even though the fingers and thumb weren't broken at all, meaning she could have easily freed herself at any time.
Mrs. Dodds: You stole the lightning bolt!
Percy Jackson: I don't know what you're talking about!
Mrs. Dodds: Give to me, now, or I will bite your heart out!
Answer: Water creature? The Hydra is a MYTHOLOGICAL creature, with many different variations in different stories. She lived in a swamp, had bad breath. This is just another different interpretation of the same Greek myth.
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