Not sure if it's been mentioned before. But for the rootin' tootin' lootin' achievement.
Orange weapons that you loot from dead zombies also count. Just witnessed my mate loot a set of orange brass knuckles and it said he got 2 out of 5. Lucky bastard is only on level 12 too
123,456 Gamerscore unlocked at 12:34:56am on 7/8/9
People that write guides without a roadmap... Why do you even exist?! Write a damn roadmap!!!