Sorry mode and cannot be missed. This was the only level that had me burning through my stash of guys to get through on Nightmare difficulty. Honestly, it was rather generous, it was just late and I was tired making it harder than it needed to be. This is a vehicle sequence that simply requires you to drive though a pipe and dodge the spinning obstacles while getting through a few boost gates consecutively. After a few gates in a row you launch at him and take off some health. Rinse/repeat.