Great Vampire

The Great Vampires were massive humanoids from Gallifreyan legend. They originated from the Dark Times.

Biology
The Great Vampires were colossal humanoids with grey skin and wings. Like lesser vampires, Great Vampires 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 steel bolt. More powerful Great Vampires needed to have their heart fully destroyed in order to kill them. (DW: State of Decay)

Reign
The Great Vampires suddenly appeared in the universe, causing mass destruction and chaos. (DW: State of Decay) The Great Vampires rampaged through the cosmos during the Dark Times. (DW: The Infinite Quest) Great Vampires created the Vampires from Earth. (EDA: Vampire Science) They may be one and the same as the Yssgaroth (FP:The Book of the War).

War with the Time Lords
Eventually Time Lords hunted these creatures down in a long and bloody war, using bowships firing mighty bolts of steel to pierce their hearts. Though the Time Lords won, they incurred heavy casualties. Even then, the leader of the Vampires escaped into the smaller universe of E-Space. After time, the records of this war were lost and passed into legend. Rassilon wrote data about the vampires that was installed into every Type 40 time vessel. It informed that one vampire, the King Vampire, had vanished and it was a Time Lords solemn duty to lay down his life to kill it. This war was said to have sickened Time Lords of violence forever. (DW: State of Decay)

The King Vampire
The King Vampire fell into E-Space. He used his great power to draw the ship Hydrax with him. The inhabitants of this ship, three humans, he turned into vampires. They fed and served him for a 1000 years until the Time of Arising. As he rose from the ground the Fourth Doctor used a Scout ship from the Hydrax to pierce his heart, killing him. (DW: State of Decay)

An alternate perspective
During the events involving Doctor's infection with Anti-Time, the TARDIS constructed a holographic projection of events from the Gallifreyan Time of Chaos. In this projection, a group of Gallifreyans were investigating Rassilon's work on regeneration, time travel, and other projects. The prime investigator was the head of the Arcalian Chapter Houses, Provost Lord Tepesh. In the course of the projection, Tepesh revealed himself to be a Great Vampire in disguise, even saying he was a direct descendant of the King Vampire.

Tepesh claimed that the Great Vampires were a peaceful lot, content to drink the blood of non-sentient genetically bred cattle, until Rassilon showed up and declared the Vampires should not be allowed to exist. The subsequent 500-year war was more one of extermination than titanic conflict. (BFA: Zagreus)

''The TARDIS declared this projection to be only partially based on reality. It is unknown how much of this projection accurately reflected real events.''