Dragon Star

A massive comet that appeared in Mithgar's skies in the late Fourth Era. Accounts of it seem to only be from the Warrows, who believed that it would be the doom of Mithgar and reported many strange occurrences, including deformed animals and widespread illness. It broke up in the sky and large parts of it fell to the ground.
It was later revealed that the Dragon Star was sent by the evil god Gyphon, as it was made of a substance that could nullify the Ban. A portion of it, later referred to as the Myrkenstone, was used by Modru to generate Winterlight, where the Foul Folk could move freely.
It is not known what happened to any other parts of the Dragon Star.