Here is the full list of all 38 Zero Escape: The Nonary Games achievements. It takes around 50-60 hours to unlock all of the achievements on Windows.
Saw the Zero Lost ending in 999.
Saw the Knife ending in 999.
Saw the Ax ending in 999.
Gained all trophies.
Finished all scenarios in 999.
Saw the Submarine ending in 999.
Saw all previews in 999.
Gained all Memories of Escape in 999.
Solved the final question in 999.
Escaped from eight rooms in VLR.
Escaped from sixteen rooms in VLR.
Escaped on Hard difficulty in VLR.
Escaped everything on Hard difficulty in VLR.
Found ALL the secrets in VLR!
Found ALL the files in VLR!
Opened the first lock in VLR.
Opened the second lock in VLR.
Opened the third lock in VLR.
Opened the fourth lock in VLR.
Opened the fifth lock in VLR.
Opened the sixth lock in VLR.
Opened the seventh lock in VLR.
Opened the eighth lock in VLR.
Opened the ninth lock in VLR.
Opened the tenth lock in VLR.
Saw any of the endings in VLR.
Saw Luna's ending in VLR.
Saw K's ending in VLR.
Saw Dio's ending in VLR.
Saw Tenmyouji's ending in VLR.
Saw Quark's ending in VLR.
Saw Clover's ending in VLR.
Saw Alice's ending in VLR.
Saw Sigma's ending in VLR.
Saw Phi's ending in VLR.
Saw the end. Or maybe the beginning?
Caught a glimpse of another time.
Saw any of the bad endings.