Born In A Dark Shadow (Warrior Cats)

BloodClan had turn tail and ran; after Firestar had killed their leader Scourge. The clan had met up at their so called 'camp', looking to Bone for leadership. But what none of the clan knew had come to be; and the only cat knowing this was Bone.
~~~
Dagger, a fierce warrior of BloodClan, had returned with an identical kit of Scourge. Bone identified this kit was Scourge's, giving orders that she/he would rule BloodClan, and take revenge for her father and claim the forest.

I don't own the 'Warrior Cat' series, Erin Hunter does.