In the vast cavern networks of the Northern Mountains dwells a creature so feared, the Hrothi just refer to it as the Terror of the Deep or - in an attempt to find comic relief - Tunnel Imp. While it uses a simple trick, to lure otherwise upside living prey into its lair, there's really nothing impish about it at all.
Several stories in height and weight of stone you could build a castle with, give this monster already an intimidating appearance, but its claws and fangs make it deadly and the tentactled snout a sheer sight of horror.
While it can't move that fast, it knows to use the light eminating from the tip of its forehead antenna not only for baiting, but even to blind and confuse its prey, so it will stumble unaware of its presence towards the lightsource until they're too close and it is too late.
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