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Ancalagon the Black is considered to have been the greatest dragon of Middle-earth, undoubtedly the largest, and is often referred to as the ‘ father of the winged-drakes ’.

He was so large that his wings were able to blot out the light of the sun, even from afar, and his body was able to crush the volcanic Thangorodrim, the highest peaks in Beleriand.

Like all other Urulóki, Ancalagon breathed fire, which was said to be hotter than any other known flame.