Fang Dragons are a particularly savage and spiky breed of dragon native to the worlds of Dungeons & Dragons. They first debuted in Dragon Magazine, appearing in the article series "The Dragon's Bestiary" in both issue #134 and #146. They returned in 3rd edition, now associated particularly with the Forgotten Realms setting; they made their debut for this edition in "Monsters of Faerun" and were then updated to a more setting neutral format with an appearance in the Draconomicon for 3rd edition.
In 4th edition, Fang Dragons were rewritten into being Gray Dragons, with the explanation that Tiamat decided the Fang Dragons were wasting their potential, so she bred a new variant with petrifying abilities and a breath weapon of corrosive slime, then set them to hunting down their inferior precursors.
Fang dragons are greedy, rapacious, and cunning creatures. Their bodies are armored with bony plates that rise into projecting spurs at limb joints and end in long, forked tails tipped with a pair of scythelike bone blades. They fly poorly, but can rise with a single clap of their wings to lunge forward. Their body plates are a mottled gray and brown, their wings are small but muscled, and their eyes tend to be glittering red or orange. Fang dragons’ heads are adorned with many small horns or spikes.
Fang dragons prefer to seek food far from their lairs, which they typically wall up with huge boulders to keep out intruders in their absence. They speak snippets of many languages and will bargain to avoid hopeless or hard battles. They are prone to random violence and outbursts of rage.
Fang dragons eat all manner of fresh meat, especially enjoying the flesh of intelligent mammals.
Fang dragons are masters of physical combat, and every part of their body is lethal. They have a disturbing tendency to play with their food in an exceedingly cruel way. They do not have a breath weapon, but have the ability to permanently drain Constitution with their bite.
Fang dragons originally appeared in the Realms in the ruins of Myth Drannor, causing some sages to speculate that they are somehow connected to the demons that have infested the ancient elven city since its fall. They are commonly found in Starwoods regions of Cormanthor, and occasionally in the Border Forest, the Spiderhaunt Woods, and other forests in the region of the Dalelands, Sembia, and the Moonsea.
(Aside from the final paragraph, this lore remains identical between Monsters of Faerun and the Draconomicon.)