Tren were humanoid in form, with scaly skin and lizard-like heads with wide mouths full of sharp teeth. Their scales were typically grey, brown, or green in color; the scales of females tended to be smoother than those of males. Tren had tails that were reported to either be vestigial or long and slender. They were bulkier and more muscular in form that either troglodytes or lizardfolk. Tren stood upright, approximately as tall as a human, and weighed on average about 220 pounds (100 kilograms).
When angered or frightened, tren naturally secreted an oily chemical that produced a stench that nearly every form of living animal found to be extremely offensive. This stench could sicken anyone within 30 feet (9.1 meters) of the tren, and even weaken those within 10 feet (3 meters).
Tren were originally bred by the yuan-ti as hybrids of troglodytes and lizardfolk. During the time period when the yuan-ti ruled Serpentes, they used troglodytes as a servitor species in their armies, but found that species' physical strength left much to be desired. So the yuan-ti utilized what they knew of sarrukh magic and bred the strongest troglodytes to he strongest lizardfolk, then treated the eggs daily with the bull's strength spell, resulting in the creation of the first tren.
After the fall of Serpentes, many tren were traded to other powerful creatures in exchange for magic and favors, but their horrific stench meant that they were often released.
- The Dream Spheres
- Ed Greenwood, Eric L. Boyd, Darrin Drader (July 2004). Serpent Kingdoms. (Wizards of the Coast), pp. 87–88. ISBN 0-7869-3277-5.
- David Cook (1991). Monstrous Compendium Forgotten Realms Appendix (MC11). (TSR, Inc). ISBN l-56076-111-3.
- Ed Greenwood, Eric L. Boyd, Darrin Drader (July 2004). Serpent Kingdoms. (Wizards of the Coast), p. 5. ISBN 0-7869-3277-5.
- Ed Greenwood, Eric L. Boyd, Darrin Drader (July 2004). Serpent Kingdoms. (Wizards of the Coast), pp. 44–47. ISBN 0-7869-3277-5.