it is a book about cats that compete to crown the whole world.
why they fight?

they fight because they have no leader for the whole world. the only leaders are the leaders in each clan.

​1. kitklan          6. eruptklan​​​​​​​
 2. runningklan  7. mountaklan​
​ 3. fightklan      8. riverklan
 4. streetklan    9. enemyklan
 5. richklan       10. furyklan 
Fun fact:

Catz (the cats that fight) climb trees like the picture above.