I am trying to get my Arc Exotic and im to the part where I have to kill so many enemies with arc skills. I saw a video to do the public event on Dreadnaught "The enemy is moving against each other" aka Loot Cave. Been waiting like 40 minuets. Nothing. Does this still work? Special way to trigger it? Can anyone help me out or tell me a better efficient way to get arc kills with hunter for quest?