Here is the full list of all 27 Call of Duty: Modern Warfare achievements.
Complete every single player mission on Veteran or Realism difficulty.
Complete all Special Operations missions.
Kill all enemies at the Church, Clocktower, and Pool without anyone calling for backup.
Burn 4 enemies with a single molotov.
Take down a flying helicopter with a molotov.
Crash a helicopter by shooting the pilot.
Kill at least one enemy while inside The Reading Place, Aural Chic, and both Subway undergrounds.
Get at least one kill with eight different weapons when completing 'Old Comrades'.
Never get hit by the sniper while escaping captivity.
Complete 'The Wolf's Den' tunnels using only the 1911.
Save Alpha 3-2 from being downed.
Complete 'Clean House' without being hit using one bullet per threat.
Only use one cinder block and bring it to the end of 'Embedded'.
Spit on Barkov.
Reach Barkov's lab entrance using only drone strikes.
Kill 3 enemies while you are on a ladder.
Blow up 3 tripwires with explosives.
Neutralize the 'Fog of War' machine gun with a frag grenade.
Kill all the enemies in the 'Embedded' field of dead bodies.
Do not injure any civilians in 'Piccadilly'.
Finish single player on any difficulty.
Shut off the power to 4 buildings in 'Going Dark'.
Kill both soldiers with one shot in 'Hometown'.
Stop three APCs with Hadir's sniper rifle.
Shoot the driver of the suicide truck.
Destroy 4 trucks with 4 drone strikes before they reach the end of their path in 'The Embassy'.
Kill an enemy with a direct hit from a smoke grenade.