Anyway, My team was the 5 Healers and 2 Warriors and me as Interrupt Ranger. The mobs you will encounter is the Jade Brotherhoods. You have about 8 mobs in total (Generally Knight, Ritualist and Mage). While the Warriors Tank in front, the ranger interrupt the mages and ritualists. While the Healers keep the Warriors alive.
I did it plenty of time and only fail 2 times..... and without my green Hornbow
... so sad.