Michel978,803 12 Nov 2014 12 Nov 2014
I find Andy UFC fan's method a little bit slower, my method was to select the mission "Hardcore!". You just need to grab the foam sword inside to start the mission, go out and straight ahead there is a box and a pop machine, break the machine and around 10-12 poppers will come out, kill them all and restart the mission. Takes around 30-40 seconds to do each time and you get 3-4% towards the challenge in each try.