Article:
D&D 4th ed: The (extinct) Ingai Race

Unlike the willowy Dyath or the large skulled Celeen, the Ingai were not a subterranean race, they were a population of forest dwelling, apelike humanoids, with long, strong limbs and large hands.

Ingai were reclusive and territorial, prone to displays of violence when agitated by outsiders, but otherwise a quiet and humble species, devoted to music, tribal society and living in harmony with nature.

Ingai crafted simple, but very effective weapons, and their skill with a simple sling was legendary. Living primarily in small shelters up in the canopy of large trees, they could pelt anything down below them into a bloody mess, long before the attackers got anywhere near them. Fleet of foot on the ground, capable of swinging through the branches, the Ingai were the fastest natural humanoids, and hunted small game by chasing it down, or by hurling a well aimed rock.

The Mind Flayers routinely enslaved whole tribes of the Ingai, using the Ingai's close knit family ties against them, they would lure them into traps, snatching the Ingai children and using them as bait was the most common tactic.

After hundreds of years, there were very few Ingai left in their natural habitat, and the Mind Flayers did not care that no Ingai could survive for very long in horrible captivity. They were hunted down, utterly dominated and used like cattle. The Mind Flayers did not care much for their uncomplicated minds, finding them bland compared to other intelligent brains, and the Ingai were relatively weak as slave laborers, growing ill and feeble if taken away from their forest homes for very long, never adapting to life underground and always the first to succumb to stress, disease or exhaustion.