Here is the full list of all 50 Metal Gear Solid HD Edition: 2 & 3 achievements worth 1,000 gamerscore.
CQC Hold up an enemy
Send Otacon a picture of the marine with no pants
Tranquilize 100 enemies
Break the neck of 30 enemies
Beat 30 enemies unconscious
Get caught by Otacon stimulating yourself
Defeat Metal Gear RAY
Defeat Solidus Snake
Take a clear photograph of the ghost image in Hold No. 2
Complete Boss Survival
Beat the Tanker and Plant chapters on any difficulty
Create the Ocelot Time Paradox
Catch a Tsuchinoko (mythical serpent)
Find every type of camouflage
Find every type of face paint
CQC Slam a guard and knock him out
Capture any animal alive
Eat a snake of any type
Submit Ocelot
Defeat The Pain
Defeat The Fear
Defeat The End
CQC Slit an enemy's throat
Kill The End before the boss battle
Defeat The Fury
Defeat The Sorrow
Make Snake throw up
Achieve a camouflage index of 100%
Complete a VR or Alternative mission
Kiss a poster in a locker
Defeat Shagohod
Defeat Volgin in a fist fight
Defeat The Boss
Finish the game on any difficulty
Disorient an enemy with a cloud of smoke from a fire extinguisher
Find Emma Emmerich
Meet Revolver
Attain grip level 3
Defeat Olga Gurlukovich
Defeat Fatman
Destroy the AV-88 Harrier II
Defeat Vamp
Hear Johnny's bowel noises in two locations
Complete all Snake Tales
Collect all dog tags
Complete all VR and Alternative missions
See all of the first-person views that are not indicated by the RB button icon
Obtain title of MARKHOR
Find all 64 Kerotans
Finish game without killing anyone