Glommus was an old, grey, blind Dragon who was one of the three guardians of the Dragon Temple of Wyrmroost. He is known for his breath weapon, a powerful sleeping mist that can make even other dragons fall asleep.
Vanessa Santoro killed him by taking control of Tanu in his sleep and slicing Glommus' throat when he got too close and then finishing the job in fully decapitating him with Tanu's Adamant-edged sword.
Later, Gavin Rose (Navarog) comes back to Glommus' gloomy lair and douses some of his crossbow quarrels and a spear in Glommus' blood, creating extremely powerful sleep-inducing weapons, with which he partly slays the Hydra, Hespera .
The rest of the party also comes back and takes some of the substance as well, for potion ingredients and weapon sedative.
- Secrets of the Dragon Sanctuary (Fablehaven #4)