It's all about the tunnels.
It was a colossal and nameless blasphemy with glaring red eyes, and it held in bony claws a thing that had been a man, gnawing at the head as a child nibbles at a stick of candy. Its position was a kind of crouch, and as one looked one felt that at any moment it might drop its present prey and seek a juicier morsel. But damn it all, it wasn’t even the fiendish subject that made it such an immortal fountain-head of all panic—not that, nor the dog face with its pointed ears, bloodshot eyes, flat nose, and drooling lips. It wasn’t the scaly claws nor the mould-caked body nor the half-hooved feet—none of these, though any one of them might well have driven an excitable man to madness.
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Hospital trip truths.