Boss event is an event, where one (or more) GM(s) will become boss(es) and attack people, who participate this event. You must kill the GM and then wait for reward. Everyone (who participated) will be rewarded. )Reward depends on difficulty and GM's Health Points). This event should be hosted everyday (only once) in Gurubashi arena. (PS: No PvP is allowed during the event, if you'll PvP you can get kicked but banned as well.)