The Duel of the Meathead Library was fought by Hiccup Horrendous Haddock III, Camicazi, daughter and heir to Big-Boobied Bertha, chief of the Bog-Burglars, and the protector of the Library, the Hairy Scary Librarian. It was fought in A Hero's Guide to Deadly Dragons.
The duel started just after Hiccup, Camicazi, and Fishlegs bumped into the Hairy Scary Librarian and just after stealing How to Train Your Dragon. The Hairy Scary Librarian demanded them to give his book back or die by the point of his sword. Hiccup responded, "These books don't belong to you they belong to everyone... well, they should," and the Hairy Scary Librarian laughed and drew two swords from his belt.
Camicazi jumped into the fight and helped Hiccup in his efforts to fight the Librarian. It was a losing battle, but Hiccup, being strong at mind, shouted out to Fishlegs to find a book called Swordfighting with Style, by Flashburn the Swordmaster. Fishlegs did as he said and hurled the heavy book at the Hairy Scary Librarian. He fell to the floor where Red Hot Itchyworms crawled over his bottom and bit into him, and he ran and screamed.
Hiccup and Camicazi won, and Fishlegs had won a gold medal in "Throwing-A-Book-In-An-Elderly-Man's-Face" in the Olympics on Berk.