Fishlegs No-Name is quite different in the books from his movie self.
Fishlegs is the only boy not to get his own dragon in the Dragon Nursery. He sneezes, waking up all of the Dragons, and Hiccup gives him the Basic Brown that he had originally caught. Later, Fishlegs is seen having reasonable success in training his dragon, Horrorcow, by using the yelling method. He is, however worried about the hunting portion of the test, as Horrorcow is very gentle.
It is revealed that Fishlegs cannot swim, and Hiccup saves him from drowning. Along with Hiccup and Old Wrinkly, he is one of the three who argued against the opening of the coffin. During the Battle of the Lucky Thirteen, later on in the Book, he is seen to be a Berserk. He gets trapped with Hiccup and Alvin in the cavern, and is amazed when Hiccup turns out to be left handed.
Fishlegs is frightened throughout the book that they will be attacked by Sharkworms. He climbs onto a Roman Galley and very nearly gets killed, indirectly causing the capture of Toothless. He is captured along with Hiccup, since the Romans can't tell which is the Heir. Alvin locks them up with Camicazi, and the three manage to escape together. A Venomous Vorpent crawls along his hand, causing the balloon to pop. Fishlegs also shoves Snotlout into the water when he tries to steal the glory.
Fishlegs has a horrible cold. He is shown to be appalling at archery and skiing, and gives a guide on how not to ski. When he and Hiccup encounter some Hysteric warriors, he goes Berserk and insults them, prompting them to chase him, and then Hiccup when Hiccup shoots their leader, Norbert the Nut-job. Later, Fishlegs goes Berserk during the Smashsticks on Ice game, insulting numerous people and prompting Hiccup to take him to Old Wrinkly, who claims that Fishlegs had Vorpentitis. Hiccup is then motivated to go to Hysteria in search of the Potato, in order to save Fishlegs' life. When he returns Potato-less, it is revealed that Fishlegs did NOT have Vorpentitis, Hiccup did. Fishlegs is the only person who understood when Hiccup asked him to shoot him, and he did, shooting him with the arrow that had been sticking in the Potato, saving his life and prompting Stoick to admit that he was wrong about him.
Fishlegs is the only person to suspect Humongously Hotshot, aside from Stoick. He comes with Hiccup on the Quest to Stop the Volcano from Exploding, bringing his Running Away Suitcase with him, which allowed Hiccup to fend off Alvin the Treacherous.
Fishlegs goes with Hiccup and Camicazi to the Meathead Public Library, complaining the whole way as usual. When Hiccup and Camicazi were sword-fighting the Hairy Scary Librarian, he bobbed the librarian on the head with a book, which may have saved Camicazi's lives, but also caused much trouble, as this action resulted in Stormfly losing her memory and the Driller Dragons being roused.
Fishlegs wore armbands for the Swimming Race, prompting all of the other Vikings to laugh at him. Snotlout poured Blubberwing goo on his head, which fogged up his glasses so that he could not see a thing out of them. This resulted in him running away from the water at first when the race started, until Hiccup and Camicazi could turn him around. The three were then captured by Norbert the Nut-job, who decided to bring them with him to America. He was rather frustrated with Hiccup's promise to the Wanderers. Later, when the ship sinks, Fishlegs saves Hiccup's life and learns how to swim in the process, as he had lost his armbands earlier. He insisted that he and Camicazi swim away from the shores of America, as he had seen something in the mist and had a bad feeling about the beach. He argued against using the Flying Machine, but went anyway, saying that Hiccup was the closest thing to family that he had. He had a very proud moment at the end of the book, when he swam up the whole length of the bay unaided with all of his tribe-mates watching.
Fishlegs is camping with the rest of the Hooligans during their search for Camicazi.
Fishlegs was given the Slavemark and sent to the Amber Slavelands. He was captured by the monster of the slavelands, and presumed dead. Hiccup manages to find Fishlegs and rescue him. It was also revealed that his mother, Termagant, was the daughter of a Murderous Tribe chief who married a handsome fisherman. When he died in a storm, the only thing that kept her going was that she was pregnant with Fishlegs. Since he was a runt, he was sent out to sea. Termagant had her dragon, a three-headed Deadly Shadow, follow her baby and take him to Hero's End. The dragon lost sight of Fishlegs in the fog and spent two weeks looking for him. Termagant passed away some time after sending her baby off. Fishlegs was later reunited with the Deadly Shadow, and is now his new dragon. It recognized his lobster claw necklace that Termagant had given him.
Fishlegs doesn't trust Snotlout when he shows up in the Murderous Mountains claiming to want to help Hiccup become king.
Fishlegs discovers the identity of his father. The "handsome fisherman" is revealed to have been Alvin the Treacherous, who considered his relationship with Termagant to have been a mere fling, and deserted her at the first opportunity, by faking his own death. The lobster necklace had been given to Termagant by Alvin, who had taken it from the coffin of Grimbeard the Ghastly. He had considered it to be a worthless trinket with which he could seduce a pretty girl. Fishlegs disowns his father and declares that he is establishing his own tribe: the No-Name Tribe, which accepts every good person.
At the end of the series, Fishlegs had succeeded in becoming a bard, as well as helped Hiccup spread rumors that dragons never actually existed.
He is rather clumsy, but is Hiccup's best friend and loyal to him. Fishlegs is shown to have a dry sense of humor and sarcastic, much like Hiccup in the film franchise.
Snotface Snotlout and the other young Hooligans are picking on him as much as Hiccup. Generally is a worrier and would rather not get into dangerous situations, but will step up when really needed.
- "Nobody's listening to you, you plankton-hearted, fish-legged, disaster area."
Fishlegs is small and skinny like Hiccup, and has asthma, eczema, a squint, a limp, and numerous allergies, including one to reptiles. He wears glasses. His hair color is never stated, but a picture of him depicts Fishlegs with brown hair.
- "[Fishlegs has] a squint that made him as blind as a jellyfish and an allergy to reptiles"
- ―How to Train Your Dragon
- Despite disowning his father, he still wears Alvin's eyepatch and carries his hook.
- The fact that Alvin is Fishlegs' father makes the latter not only a great-great-grandson of Grimbeard the Ghastly, but also Hiccup and Snotlout's cousin as well. This makes him their third cousin.
- Fishlegs' last name was revealed in the final book, No-Name, due to the fact he washed up on Berk as a baby and did not have a family name. Coincidentally, one of Eret's men is called No-Name.
- Fishlegs in the books is very similar to Heather.
- Both were separated from their families at a young age.
- Both have objects from their parents. Fishlegs had the lobster claw necklace, Heather has her horn.
- They both have some Berserk connections. Fishlegs is half Berserk on his mother's side and Heather is originally from the Berserker Tribe.
- Both are related to one of Berk's greatest enemies.