Red dragons ranging from brilliant blood red to dull terracotta, powerfully built with heavy-jawed heads and thick muscular bodies

Mountain dragons are red in color, ranging from the brilliant blood red of a hatchling to the dull terracotta color of an ancient individual. These dragons are powerfully built, with heavy-jawed heads and thick muscular bodies, yet their necks are still long enough to give them the legendary flexibility of a true dragon. They are cruel monsters, actively seeking to hunt, torment, kill and consume intelligent creatures. They are often said to prefer women and elves, but in truth a mountain dragon will attack almost any creature less powerful than itself. They are intelligent and self-assured, but also impatient and overconfident. One will often plan strategies in advance and then choose one at random when facing unknown opponents, without regard to whether or not the strategy is likely to work. The sheer power of a mountain dragon is often the only reason one is still alive. Mountain dragons are immune to normal fire, and suffer only half damage from magical fire.

Adult red dragons are tyrants that claim vast domains and might command armies of followers or significant magical resources. Red dragons rarely pay attention to the nations and claims of smaller creatures, and they might consider entire cities part of their realm. Most red dragons are inattentive rulers, though, spending decades focused on their own comforts, hoards, or magical concerns within their lairs. But when their attention returns to their territories, if they find matters not to their liking, whole lands might burn.

Ancient red dragons number among the most feared and destructive beings in the multiverse. Few can withstand the wrath of an ancient red dragon that turns its mind toward devastation. These dragons' greed matches their ruinous potential, and they collect vast hoards studded with storied treasures and magic items. Their lairs frequently tap into volcanic depths and might pierce other planes of existence, bringing servants from the Elemental Plane of Fire or the Lower Planes into their service.

Red dragon wyrmlings are born destroyers. From a young age, they delight in igniting objects and creatures alike. They sometimes restrain themselves from scorching creatures to instead bully others into following their orders and bringing them gifts.

Young red dragons number among the most unpredictable of their kind. They seek territories rich with treasures and potential followers, raiding, burning, and slaughtering to enforce their will. Unless these dragons meet significant resistance, they cement their power and begin reigns of terror that can last for centuries.

The archetypal red dragon is Smaug from "The Hobbit"

The archetypal red dragon is Smaug from "The Hobbit." Red dragons usually (80%) speak, sometimes (40%) cast magic, and will sometimes (20%) be found asleep. If the dragon is asleep, there is a 1 in 6 chance that it will awaken in the presence of adventurers. Dragons also sometimes feign sleep.