Boss Endurance Mode is available for players level 30 and up. You can only fight by joining a guild. There is currently one boss available to fight.EditUpon defeating Octavious, the guild members will receive 50+ guild coins (depends of damage rating 1st place 1000gk 2nd 800, etc) guild coins (+50 if defeated within a certain time). These coins can be used to buy equipment, EXP books, and soulstones within the guild store.
While killing Octavious, it is possible you will 'recover' loot, such as Holy Neck Rings, Dragon Armour, etc. You can request one of the recovered loot by pressing the reward button at the Octavious battle screen. If there is an item available to distribute, it gets given to the person in the first spot on the request queue every hour. You may only request one item at a time.