Naga
Monster Rancher Metropolis: Monster Rancher DS Archive (DS): Monster Rancher DS: Monster Rancher DS FAQ: Unlocking the 12 Locked Breeds: Naga
By Thorr on Tuesday, August 10, 2010 - 06:46 am:

Breeder Rank: S
Monster Rank: S
Location: Tournament

Win the Big 4 tournament on 9/1 to unlock Naga.