- "There are Riproarers - horrible creatures that dribble and scream."
Riproarers are cave dwellers first appearing in How to Steal a Dragon's Sword as one of the first dragons to join the Dragon Rebellion.
Riproarers are quadrupedal dragons with one pair of wings. Their legs are long and their skull appears rather flat on top.
There is some variation with their coloration. In How to Steal a Dragon's Sword they are described as greenish, but in The Incomplete Book of Dragons, they are depicted as purplish. They also have acidic blood.
- "Black frothing slobber foaming at the mouth; red-veined eyes quivering; its hot, indescribably stinking and repellant breath scalding Hiccup's cheeks."
- ―How to Steal a Dragon's Sword
A group of Riproarers is referred to as a Swarm.
Riproarers can squeeze themselves into spaces as small as a human hand, due to a collapsible skeleton. Even their skulls can flatten, with sections sliding over one another. They share this ability with one other related dragon - the Raptortongue.
A Riproarer tears its victims to pieces, but might let you alone if you have recently eaten parsnips, as they find this root vegetable repugnant.
The Riproarers are discussed in this reference book.