Garffiiljorg (or simply Garff) makes his first debut in the Tone Death. He later returns as an adult dragon in Living on the Edge and No Dragon Left Behind.
The Dragon Hunters had found Garff when he was still an egg. When the Riders showed up, they launched the egg so they could make their escape while they saved it.
While Fishlegs and Hiccup couldn't figure out what kind of egg it was, Tuffnut's Chicken sat on it to keep it warm, despite it being much larger than she was. Surprisingly, Garff hatched from the egg shortly after, only to start crying and screaming. The Riders were annoyed by his screams, not knowing how to calm him down.Tuffnut came up with a name for the baby dragon and they put him in one of the dragon stables for the night. Garf finally stopped crying after Chicken "sang" to him, only for him to respond by blasting her with amber and trying to eat her. The Riders were horrified to learn that their new dragon was a baby Death Song.
The next day, the Riders wanted to get rid of Garff (especially Snotlout ), but Heather refused, knowing exactly what it's like to be alone. Snotlout decides to take him to Melody Island, but Hiccup reminds him of what happened the last time they were there. Heather begins to sing to Garff, which puts him to sleep, along with the twins and their dragon. Hiccup then realizes that singing might not just be a way that the Death Song draws in prey, but also to communicate. This gives the Dragon Riders the idea that they all should sing to Garff to help train him.
Unfortunately, Garff still blasts each rider, except Heather, with amber regardless of whether or not he likes their songs. Seeing that their method isn't working, Hiccup and riders decide to take Garff to Melody Island and find the adult Death Song. They keep the baby dragon quiet with a combination of Heather's singing and Dragon Nip.
Once they arrive, they find that the Death Song managed to escape the cave that Hiccup and Earsplitter trapped him in, and are soon attacked by him. Garff flies over to the older dragon and cries. The Death Song approaches him and begins to sing. Garff responds with his own song, but the dragon whacks him into a cliff wall with his tail. Hiccup realizes Garff is singing the songs the Riders taught him and the Death Song doesn't like them. They all trying singing others songs to calm the older dragon, but to no avail. Just as he is about to attack, Garff flies back to protect them and begins to sing. This time, the Death Song accepts Garff's song and flies off with his newly adopted child.
After having reached adult or near-adult size, Garff is attacked by the Dragon Hunters under Krogan and left to die while his "parent" is captured for use in capturing Singetails in "Living on the Edge". Astrid and Stormfly stayed with Garff and were able to nurse him back to health.
Garff eventually ends up moving to Dragon's Edge after this and bonds closely with Stormfly and Astrid.
Having taken up residence on Dragon's Edge following the Dragon Hunters' attack, Garff becomes a problem when he begins attacking other dragons in "No Dragon Left Behind", with the exception of Stormfly, who is his best friend and has become immune to his song. This eventually prompts the riders to attempt to relocate him to a new island, only to find it home to a pack of Slitherwings that capture Garff and seemingly poison Stormfly.
However, in reality Stormfly is mourning Garff's apparent loss, as Garff's amber was unable to cling to the poison-coated hides of the Slitherwings. Garff is able to protect himself from their poison by encasing himself in his amber, and is eventually rescued by the riders, who soon relocate him to another island where he and Stormfly bid one another goodbye.