To be honest, I didn't find much of it too hard. The hardest parts for me though, was the city 17 strider battle and why was the turret section too hard? just put the turrets at the entry Points and then go into hiding with just one angle they can come from and take out the shotgun. What also could qualify as hard was when I was beating ravenholm, and I was 100% on to beating it with gravity gun only. It turned bad when all those skinny zombies came and I was supposed to wait for the elevator, I ran out of shit to throw at 'em pretty fast. I had to try and kill them with shards from the broken wood box...