Great Vampire

The Great Vampires were massive humanoids from Gallifreyan legend. The came from the Dark Ages.

They may be one and the same as the Yssgaroth (FP:The Book of the War).

Physical Description
The Great Vampires were colossal humanoids with grey skin and wings. Like lesser vampires, the Great Vampire required blood to survive, but due to their large size they needed considerably more. Great Vampires were extremely powerful and one individual could drain a whole planet dry. They had the ability to absorb energy, such as from weapons, and were able to survive numerous minor wounds. The only way to kill one was to stab them through the heart, usually with a iron stake.

History
The Great Vampires suddenly appeared in the universe, causing mass destruction and chaos. The Time Lords hunted these creatures down in a long and bloody war, using bowships to pierce their hearts. Though the Time Lords won, they incurred heavy casualties, and even then the leader of the Vampires escaped into E-Space. After time, the records of this war were lost and passed into legend. (DW: State of Decay)