I have played this game for so many hours over the years since its been out. For a good 2 years the only trophy left for platinum was the get 200 kills in mp. I really dislike that gamemode. Finally decided to go and get that last trophy yesterday. And it was the best time i had in battlemode. Finally all the super sweats stopped playing it.. and i finally got the best and my personal favorite single player shooter ever platinum!
I have played through all three sets and both on hard settings and still don't have anything close to what achievements he's talking about. Steam is broken.