so....there is another chest...the 6th chest...after the platform jumping down to the atheon entrance there are more platforms you can take to a small area with a chest(you can easily see this area for yourself minus the chest) i am pretty sure to get this chest no one can die in the entire raid up to this point....not 100% confirmed yet but the chest DOES spawn....just not positive on what causes it too spawn.....please keep this thread going and add anything you may have noticed so we can solve this mystery chest once and for all =)™