A grown Glacier-Drake is as long as a river barge and as thick through the body as a cart, a heavy, legged serpent with four short, broad limbs ending in flat, ridged claws for scraping ice. Its scales are pale blue-white and translucent at the edges, so that through clear ice a watcher can sometimes see it pass as a long, dim shape. It has no eyes, only smooth, scaled hollows where eyes would be, and two pits on the snout that sense warmth. Its jaws are long and lined with rows of short, blunt teeth for crushing. It moves slowly and steadily through the ice, and its passage can be heard above as a deep grinding and, now and then, a crack like a gate splitting.

They live within the glaciers and under the frozen seas of the Frost-Bound, each alone in a wide maze of its own tunnels, and come near the surface only to feed.

A Glacier-Drake hunts from below. It lies in the ice until it senses warmth above, a beast, a traveller, a camp, and then tunnels upward and breaks through beneath it, seizing what it can and dragging it down. It does not chase, and it does not hunt on the open surface. It is slow to anger and slower to give up.

It bores through solid ice by scraping and crushing, leaving tunnels that the cold slowly seals behind it. It senses heat through great thicknesses of ice and can tell a large warmth from a small one.

A Glacier-Drake lays a few eggs deep in the ice and leaves them; the cold keeps them, perhaps for ages, until something warm comes near enough to wake them. They grow slowly and, as far as anyone knows, without end.

Its old tunnels are sometimes used by the Frost-Born as shelter and roads, and its scales make cold-proof plates. Its danger is the ground opening under a warm traveller, without warning.

Travellers who have heard the grinding under the ice tell of the ice-worm, a beast as long as a road, and the stories have only grown with the telling. The advice that comes back with them is sound: on the deep ice, light no fire and sleep apart.

Delvers who cross to the Frost-Bound for preserved relics tell of a camp that lit one fire on the deep ice and went down through it in a single heave, fire and all; the relics they came for lie under the ice with them.