From publisher blurb:
In the dark, wild places far below the wave-flecked flanks of a forlorn, wave-lashed island lurk the degenerate troglodytes of the Ebon Lake. Dwelling amid the tumbled cyclopean ruins of a forgotten epoch, the troglodytes toil in their labyrinthine, stench-filled caverns at the behest of their bloated, tentacled master. Emerging on fog-shrouded nights when a sullen, gibbous moon hangs low in the sky, the troglodytes raise their croaking voices to the ebon heavens in terrible, half-forgotten rites of veneration to unknown, elder beings.
Designed for the Lonely Coast campaign setting but easily adapted for virtually any other setting.
This System Neutral Monstrous Delve presents the Troglodytes of the Edon Lake, along with a detailed overview of their lightless lair.