Warriros - Rise of Scourge.

This is a book called Rise of Scourge.

It was about a cat called Tiny who was born to be a kitty pet under size.
One day he crosses a forest with wild cats defending their territory, Tiny is left with scars and leaves his home to find a new life. He changes his name to Scourge and leaves his past behind him - except his deadly desire for revenge. Blood is everything!