Question: why did emhyr attack cintra?
Answer: Basically Emhyr was once named Duny and he married the princess of Cintra, they had a child Ciri. ... So he attacked Cintra and tried to kidnap Ciri. No one knew Emhyr was also Duny - Ciri's father. His intent was to kidnap Ciri, marry her, and have a child with his own daughter.