These monstrous sharks sport massive wings allowing them to extend their hunting range to land and air. Storms provide them with ideal hunting conditions as the heavy wind and rain provide cover for their sneak attacks. Terlen often attack in flocks that ambush prey and tear them apart using hit-and-run tactics. They prefer vulnerable targets in the open and use their speed to prevent the victim's escape.
The terlen's origins are a mystery, but it is thought to originate from the oceans of the lower planes. Its wandering nature and flexible means of locomotion allow it wander from one plane to the next and even occasionally enter the material plane. Other times terlens are summoned by powerful beings such as sea gods who wish to unleash these monsters on mortals who foolishly believe they can avoid the ocean's wraith by staying inland.
Some mortals summon terlens in an attempt to utilize them as an all-terrain attack force or even as mounts. Though this often results in the summoner being torn to shreds, those who succeed can bring a terrifying strike force to bear against their enemies.