"all it takes" is something quite difficult to do. you are basically asking 100+ players to not attack something.
That will very rarely work. when one person aggros it, nearly everyone wil be thinking "oh shit, if that guy attacked it, everyone else will to" and he will attack it because he doesnt want to lose credit. when 100+ people think that, 100+ people will attack it at once.
thats just how it works.
