Survivors (Erin Hunter). Original series

"Lucky and the rest of the Leashed Dogs have settled in the forest--but a vicious Pack has claimed the land, and will stop at nothing to ensure that it is theirs alone"--

Lucky and Alpha have finally reached an uneasy peace. But as the newly united Pack sets off in search of a home far away from the Fierce Dog camp, they discover that no territory is truly safe. Another group of dogs survived the Big Growl--and this new Pack may be their most dangerous enemy yet.

"Lucky and the dogs of the Wild Pack must fight tooth and claw to survive the storm of dogs--the terrifying battle that has been haunting Lucky's dreams"--