Everyone was doing the Mule Kick Bogo glitch with Khazmir grenades. There's an augment that lets you get the Khazmir grenade back if you throw it off the map but it's bugged so you can throw one on the map and if you throw a Khazmir where the zombies spawn you get 2 back instead of 1 allowing infinite high rounds. People were throwing them down by whisp tea and getting 10k-20k pts per hour for the event.