A behir was often mistaken for a wingless blue dragon. It had a long, snake-like body and could slither on the ground like a snake, but it also had six pairs of legs upon which it could walk or climb if it chose to do so. Each of a behir's twelve feet contained three clawed toes. They began life with six or eight legs and grew additional legs as they aged. They grew about 8 feet (2.4 meters) per year.
Newborn behirs were about 2 feet (0.61 meters) in length, while the typical adult behir was around 40 feet (12 meters) and weighed about 4,000 pounds (1,800 kilograms). Behirs reached adulthood at the age of ten and like other reptilian creatures would continue to grow throughout their lifetimes, having to shed their scales periodically.. Because of this behirs could sometimes reach gargantuan sizes.
Behirs could breath a magical burst of electricity from their mouths, much like a blue dragon. (They themselves were completely immune to damage from electricity.) There were some reports that they were immune to poisons as well.
If a behir grabbed a hold of an opponent or prey with its mouth, it had several options. It could wrap its body around the victim and constrict, it could tear at the victim with its many clawed limbs, or it could simply swallow the victim whole.
- Halruuan behir
- Halruaan behirs were a miniature species native to Halruaa, where they were bred as pets or guardians.
Behirs were usually solitary creatures, but could be found in mated pairs, though this only lasted until their eggs were hatched. They were most active during the day. And during the winter months they hibernated.
Mating took place in early spring. Females produced between one and four blue-green, leathery eggs, which were buried under dirt or sand. There were conflicting reports about how long it took for their eggs to hatch. Some sources claimed it took eight months for them to hatch. Others insisted that it only took three or four weeks. The young were driven from the den soon after hatching.
Behirs preferred to live in warm, hilly terrain. They made dens in caves—which were often in the side of high cliffs—or hidden thickets. A behir's territory usually encompassed an area of 400‑square-mile (1,000,000,000‑square-meter).
Behir horns could be used to make the ink necessary for scribing a magic scroll for a lightning bolt spell. Similarly, a scroll of neutralize poison often used ink from a behir's talons, and that of protection from poison used ink made from a behir's heart.
Behir scales were sometimes used to make armor, much like the hides of dragons.
- The lamia noble Transtra kept a behir as a companion, although she had to charm it to do so.
- Grimlight was a behir who lived in a gorge near the Cold Vale.
- Longjaws was a powerful behir who served the lich Alokkair.
- Vozhin was a behir who lived in the corpse of the primordial Petron, in the world of Abeir.
- Eric Cagle (July 2005). “The Ecology of the Behir”. In Erik Mona ed. Dragon #333 (Paizo Publishing, LLC), pp. 56–60.
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