Nightshade's Thirst (Vampire Warrior Cats)

Nightshade grew up in ThunderClan but is a half-clan cat. Her mother was in ThunderClan, and her father is in RiverClan. Nightshade goes on a hunting patrol, but while she is hunting she spots two strange cats. They go by the names, Bloodfang and Whitefang. Nightshade asks what they were doing on Thunderclan's territory. They say they're on an important mission. But what is that mission?

(Still in the process of editing)