Warriors: Two Halves

'Two halves will make two new.' Brightfur and Oceanblue both receive a strange prophecy from the legendary Firestar. Then, the three ancient clans come back to the forest and the clans are in for a surprise. The three ancient clans are willing to join the four clans as warriors. There are too many cats in the clans and not every clan thinks that it will survive. RiverClan finally decides to try and overpower the other three clans with the help of the Dark Forest. Will the clans survive? And who are these ancient clans?