Create a monstrous snowy dragon with cracked ice scales, glowing blue eyes, and frost-covered spikes along its spine. Its wings are torn, made of icy membranes with icicles hanging. Steam-like cold vapor comes from its mouth and nostrils. Its tail ends in a frozen spiked mace, and its claws are long and blackened with frostbite. Add broken chains on its legs, scars from old battles, and snow-covered textures across its body. Style it as a dark fantasy boss dragon emerging from a blizzard with a terrifying, ancient look.