Call of Duty: Black Ops II

I got this achievement easily by using the special weapon the Storm PSR as you can customise which guns you use in a mission after completing the game once on an easy difficulty, with this gun it's easy to kill enemies without being shot at yourself as it allows you to shoot through walls and objects.

The missions you have to complete for the achievement are

Celerium
Fallen Angel
Karma
Achille's Veil
Odysseus
Cordis Die
Judgement Day.

You don't have to complete the Strike Force missions on Veteran for the achievement.

OK, not a solution but am posting this as it may save some people a lot of wasted time. Having just wasted a couple of hours of my time trying to progress on this. In reference to the Veteran play-through (not sure if it occurs on easier difficulties)

When you get to the the Cordis Die mission and reach the point of choosing either sniper or rappel - choose SNIPER.

If you choose rappel you will not be able to get progress beyond the driving section at this time as the mission will fail with the presidents death no matter what you do.

Not sure what caused this glitch (whether it was always there or after the title update but either way it's sloppy coding from Treyarch), and hopefully they will uncover it and rectify it at some point but in the meantime hope it helps somebody.

When you load the Game up, Select 'Campaign'

Providing that you have completed the Story already select 'Replay Mission'

From this Menu, you can select Which mission you want to play.

Select the Mission you want and Change the Difficulty to 'Veteran'

This Menu, you can Change your Loadout to whatever you want.

I suggest using the: Storm PSR
M8A1 - Attachments: Milli Scanner
Supressor
Extended Clip

Grenade
Semtex


Perks: Access Kit
Quickdraw
Fast Mag


The reason why I suggested the Storm PSR is so that you can Hide behind Cover where you are safe from Enemy Fire, and yet you can still kill them. The M8A1: So you can quickly 'Snap' onto Enemies at Short/Medium Range. (Using LT to aim, and RT to fire) Whats also good about the M8A1 is that it is Burst-Fire, Keeping the Recoil to a minimum! :)


Take each level Slow, Making sure that you use the M8A1, and Storm PSR effectively. Before advancing to the next area, Make sure all Enemies have been eliminated.


The Levels/Missions you need to complete for this Achievement are....Celerium
Fallen Angel
Karma
Achille's Veil
Odysseus
Cordis Die
Judgement Day.

To check which levels you have completed on Veteran Difficulty, At the 'Replay Mission' screen...Press 'X' to view your 'Combat Record', On the 'Overview' tab, Select the Mission you think you may have completed, and at the bottom of the Screen (Where it says 'Difficulty, Challenges, Robot/Vehicle Kills, Explosive, Stun) Under 'Difficulty' you can see what missions you have done on Veteran.


Please comment what I can do to make this Solution better before voting Negative....Thanks!