Emberwyrms are a type of skeleton dragon typically raised by the Scourge from the corpses of red wyrms to serve as powerful minions, as seen in . They appear similar to the magmawyrms formerly of the black dragonflight.
Nightbane in Karazhan may be a type of emberwyrm, as he appears as a fiery, skeletal dragon. In life he was a blue dragon, Arcanagos, raised into undeath; appearances aside, this suggests he is a frost wyrm. It could be, however, that the spell used to kill him could have altered his undead appearance.