Terrible Terrors have a Propane based fire.
Deadly Nadders have a Magnesium based fire.
Speed Stingers do not breathe fire.
The gills of Singetails are located on their bellies.
Singetails can shoot fire out of their mouths, gills, and tails.
Although a Scauldron breathing fire has never been recorded, it has been reported that the smell of flammable gas can usually be smelt before a dragon fire attack has been smelled around them.
The Red Death Hiccup defeated was in its Titian Wing stage.
The Red Death’s fire is Methane based.
In pack formation, a steady stream of fire from Night Terrors can join into a massive fireball
Because their fire is based on a Kerosene gel, Monstrous Nightmares keep themselves covered in their spit so that can light themselves on fire at will. They will normally do this when cornered.