Congratulations, enough ender essences have been collected to resurrect the ender dragon!
The summoner is now performing the resurrection ritual, and will be finished around this Friday, 7:00pm server time! At that time, the end world will be reset and a new dragon will reside in it, waiting for you overzealous adventures to once again slay it.
The event will remain running for the next couple of weeks, with a new goal of 100k essences required to summon a second dragon. So there is still time to collect the special event loot.