Jaculis was a tree-dwelling creature that resembled a snake.
Jaculis looked like snakes with mauve to dark purple scales and an arrow-shaped head topped with sharp, forward-pointing horns.
Jaculis could live in nearly any environment, but were most often found in warm forests.
Jaculis could change the color of their skin to match their surroundings. They were talented climbers and swimmers.
Jaculis lured in their prey with animal trance, then attacked with its sharp horns and its ability to constrict. If a foe proved too troublesome, jaculis jumped from tree to tree to escape, then swung around and pursued the prey for a better opportunity.