Here is the full list of all 50 Spec Ops: The Line achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Play it smart.
Complete three chapters in a row without being killed or reloading a checkpoint.
Complete any chapter with 60%+ accuracy without dying or reloading a checkpoint.
Live and let die.
Complete game on "FUBAR" difficulty.
You are relieved.
Choose vengeance.
Kill an oryx. (campaign only)
Show mercy.
Stun an enemy by dumping sand on their head. (campaign only)
Follow your orders.
Kill 50 enemies with grenades. (campaign only)
Recover all Intel Items.
Live and let live.
Complete game on "Walk on the Beach" difficulty.
Complete game on "Combat Op" difficulty.
Complete game on "Suicide Mission" difficulty.
Carry on, soldier.
The end of the line.
Choose restraint.
Blow up 10 explosive objects, killing at least one enemy each time. (campaign only)
Kill 150 enemies with any heavy weapon. (campaign only)
Get out of here!
Kill an Edged Weapon Expert while he is up to 5 meters away. (campaign only)
Kill 350 enemies with any rifle. (campaign only)
Stand united.
Kill 75 enemies with any shotgun. (campaign only)
Kill 50 enemies with any sniper rifle. (campaign only)
Kill 10 enemies while they use zip lines or are rappelling. (campaign only)
Save a bullet.
Kick an enemy by vaulting over a cover. (campaign only)
Kill 250 enemies with headshots. (campaign only)
Kill 50 enemies using only the Attack Command. (campaign only)
Buck the chain of command.
Recover 12 Intel Items.
Kill 100 enemies with any pistol or SMG. (campaign only)
Play it loose.
Hit 10 enemies with your melee attack. (campaign only)
Kill an enemy by tagging him with a sticky grenade. (campaign only)
Face the horrors of war.
Kill 4 enemies with a shotgun in 10 seconds or less. (campaign only)
Engineer an exit strategy.
Kill an enemy just as they are throwing a grenade. (campaign only)
Sprint into cover 10 times while under fire. (campaign only)
We have contact.
Kill 3 enemies with a single grenade. (campaign only)
Look out below.
Kill 5 enemies using blind fire. (campaign only)
What's lost is found.
Recover one Intel Item.