World Bosses

It appears that a portal has been discovered that breaches the realms of raiding and the safezone!   
Mystery Skulls are the broker to this madness but also the map to fortune.   
These can be obtained through raiding or from Dodgy Tyrone and his black market. (How he got his hands on these, we don't know!)   

Upon use of the skull, a portal will open at your feet and the boss will announce itself and that it will arrive in 5 minutes!   
Make sure you are prepared because these guys brought their A-game this time.   
Their attacks seem to have broken limiters in the safezone and will dispose of you if given the chance.   

Dealing more damage to the boss will increase the loot you receive after the boss has been defeated.   
Mystery Skulls can be combined with mystery bait for a special boss skull.