Nicky explains that thousands of years ago, a sect of vampires called the Tribe developed that, unlike other vampires, feasted on humans, and later, other vampires, altering them physiologically and mentally, becoming ferocious creatures whose strength dwarfed that of normal vampires. Unlike normal vampires, they procreated, and their children were mostly abandoned, murdered or devoured. They eventually turned on each other, and a myth began that they fell into hibernation, and would only be awakened by the smell of one of their own. It was feared that some of the Tribe's abandoned children would be found and raised by humans, their true nature remaining dormant as long as they did not feed on blood. Adam is apparently a descendant of the Tribe, and when Josh and Nicky altered him, this awakened a dormant member of that race, which came for him, attacking Josh because Adam's blood smells like that of his maker.