I had been half-expecting this eventuality, but it still made me jump. The Goblin tongue is a rich and immensely expressive edifice, full of sonorous complexities and subsonic tonalities. From the vast mouth and keen intelligence of an Old One, even our own language is transformed from everyday richness of expression into a towering and elaborate gothic construction of implicit references and implied commands.
So there was no way that any of us could not obey the summons contained in that single word. As one, we turned and walked into the open doorway without conscious thought, at least on my part. It was as if my legs were suddenly under the command of another, more ethereal entity. I shook my head and the feeling of remote control disappeared as quickly as it had appeared. I still wasn't going to walk in any other direction just now, mind you.
Inside the doorway was a large open space, roughly circular. It was not like the immense chamber outside, of course, or even one of the Goblin caverns, but still large enough to be comfortable for a creature that could fly. The walls and ceiling were of the same irregular stone as the cave outside, with red glowing patches dotted about irregularly. The floor was glassy smooth and pale, almost white in colour with an almost imperceptible translucency that hinted at some vast movement within, but didn't quite reveal it, and formed into a shallow bowl.
In the exact centre of the floor, as far as I could tell, was a dome perhaps a hundred feet across and half that high, a hemisphere apparently of the same material as the floor and with a raised dais merged seamlessly at one side. A large creature was lying on the platform; in the flickering red light, we caught our first glimpse of the missing Old One. It was curled up like a cat, with its tail wrapped around its haunches and its wings folded at its sides. Only its vast head showed any sign of movement and its alert eyes watched the three of us as we approached.
From my very limited experience, the Old Ones preferred a raised platform on which to rest, the rock subtly formed underneath them to align with their own contours, in the way that the very best mattresses formed themselves to bodily curves. This was an example of their astonishing ability in the arcane skill of fluid masonry; any of their kind could cause solid rock to soften and flow to form plastic shapes at their command.
Why they like to rest on such a platform is a very different question. It's not like they need the extra height to look down on mere Goblins. Every Old One I had encountered was fifty feet or more from nose to tail, with a long and sinuous neck that would allow it to look down on almost any creature on or under the surface. Perhaps they just don't like the drafts.
There is no doubt that the Old Ones are always an awesome sight to behold. They are said to be difficult to tell apart, at least to Goblin eyes. This one might have been slightly smaller than the other one - or ones - I had encountered. The true colour of its scales was difficult to determine, glowing as they were in shades of red reflected from the walls. The curve of its neck and the set of its haunches might have been a little different from what I remembered. I couldn't be sure.