Collect every type of weapon

Sneak up on The End and hold him up

Blow up a munitions shed with TNT

Poison a guard

Put an enemy in a locker

Clear the game without entering Alert Mode (not including events where Alert Mode is mandatory)

CQC Interrogate an enemy

Finish the game on any difficulty

Defeat Shagohod

Use a knife to remove a bullet

Make Snake throw up

Defeat The End

Defeat The Pain