Here is the full list of all 49 Deus Ex: Human Revolution achievements. It takes around 40-50 hours to unlock all of the achievements on Windows.
You watched the entire credit list and saw the surprise at the end.
Complete Deus Ex: Human Revolution.
Complete Deus Ex: Human Revolution at its hardest setting.
You defeated Zhao Yun Ru and by doing so, destroyed the Hyron Project.
You pointed out the flaws in his logic to millionaire Hugh Darrow.
You defeated Jaron Namir, Leader of Belltower's Elite Special Operations Unit.
Perform 50 takedowns within the same playthrough. (Civilians don't count.)
Descend into the bowels of an urban jungle and confront a warrior-priest.
You convinced Mengyao to spill the beans on the mysterious Hyron Project.
Protect a client's interests by performing a less-than-hostile takeover.
Against all odds, you saved Faridah Malik's life.
Help Officer Nicholas take out the trash.
Follow Pritchard's lead to uncover the truth.
You defeated Yelena Federova, elite member of a secret mercenary hit squad.
It may take some sleuthing, but justice must be served.
You really nailed your case against Lee Hong.
Help a lady in the oldest of professions clean house.
Help the Hive Bartender settle a tab.
You sent Diamond Chan on the trip of a lifetime.
Fully upgrade your first augmentation of choice.
You convinced a fast-talking bartender to let you see Tong Si Hung.
You made it through an entire hostile area without making so much as a squeak.
Successfully hack at least 50 devices within the same playthrough.
You had an argument with your boss, David Sarif, and won.
Deal with the man in the shadows.
You defeated Lawrence Barrett, elite member of a secret mercenary hit squad.
Put a grieving mother's doubts to rest.
You kept Megan's bracelet for yourself. Apparently, letting go really is the hardest part.
You convinced Wayne Haas to let you into the morgue.
Deal with Mr. Carella's indiscretion.
Upgrade your first weapon of choice.
You convinced Zeke Sanders to let his hostage go.
Perform your first Hack successfully.
Perform your first Takedown. Civilians don't count, so be nice.
Knock out at least 100 enemies in a single playthrough.
Experience all the different endings that Deus Ex: Human Revolution has to offer.
Complete Deus Ex: Human Revolution without anyone dying by your hand. (Boss fights do not count.)
Complete Deus Ex: Human Revolution without setting off any alarms.
Read all 29 unique XP books within a single playthrough.
Fully upgrade one of your weapons.
You found all the hidden story items in Megan's Office. Point-and-Click much?
You convinced the smooth-talking politician Bill Taggart to tell the truth in public.
You talked Doctor Isaias Sandoval out of suicide.
You found and read the secret message. Now you know too much...
Greedy bastard. You accepted O'Malley's blood money and let him go.
You paid poor Jaya's debt in full. How very... humane... of you.
Maybe next time, Jacob will use a more complex code when arming a bomb.
You granted a dying man his final request.
Seems you like playing with balls, eh?