If you are worried about getting this on your playthrough, worry not. You will have a great opportunity (only opportunity?) to do this on the last level. When are making your way through caves and your suit is all messed up, rebooting, you will eventually come across a machine/beam thing you interact with? Prophet says "do you need to become more Ceph than Ceph?!" that is when you become supercharged for a pretty decent amount of time. There is more than 10 enemies to kill. There is a reaper cannon there a Ceph sniper rifle cannon, those become supercharged when you become charged. So pick one of those up and get to killing as fast as your can. You get a few chances so don't freak out if you don't on your first, but I found the 2nd chance didn't have too many enemies. The last chance seemed to last a long long time but didn't see quite the abundance of enemies as the very first chance.