- Load this save (its the last level)
it will pop these achievements:
All Melee, All Handguns, All Assault Rifles, All Shotguns, All Heavy Weapons,
1st kill*, and First Headshot*.
- Beat the last level and these achievements will pop:
Professional, Expert, Normal,
1st Mission*,
All Sniper Rifles**, All Weapons**
(*Hopefully you won't need these because it will look wierd if you didn't get these achievements a long time ago.)
(**Make sure you collect the Custom Sniper Rifle, then After you beat the last level, beat any other level. easiest is 1st level)
Also, if you need help beating the last level, use this:
http://www.youtube.com/watch?v=R9TLEpFCfQg
(NOT MY VIDEO just very helpful)
Also after you beat the last level, make sure you don't skip scenes or the credits.
Doing so may make Expert and Normal NOT pop.
If Expert or Normal STILL don't pop, replay the level without skipping scenes or credits.