A Glean is a limber, ferocious creature that at its maturity could easily dwarf even the densest of forests.
Carnivorous, and with an appetite that only grows to match its ever-swelling size, it hunts, slithering, silently, furtively, its flexible skin seamlessly adapting to the color of its environment. Spotting food, the Glean would silently unleash a toxin into the air through its many pores, paralyzing its prey before inevitably consuming it whole and alive.
Due to their almost insatiable appetite and immense size, a Glean could easily devour dozens of creatures of every shape and size within a single day and still have enough of a craving and space for even more.
For the Elves, with their keen senses, their unmatched strength, should one ever encounter the other - it was the perfect hunt.