Full list of all 60 Batman: Arkham Origins achievements. It takes around 80-100 hours to unlock all of the achievements in the base game on Windows.
The base game contains 50 achievements, and there is 1 DLC pack containing 10 achievements.
Finish I Am The Night Mode
Earn a level of prestige in multiplayer
Reach max overall level in multiplayer
Reach max level with the Bane faction in multiplayer
Reach max level with the Joker faction in multiplayer
Obtain all the medals on Custom maps in Challenge mode
Win a round of each map with each faction in multiplayer
Obtain all medals on the original Campaign maps in Challenge mode (as Batman)
Complete Deathstroke without failing a single counter
Scan 20 Anarky Tags
Kill a Hero to bring back your entire gang when at 0 reinforcements on a full multiplayer server
Obtain all medals on the original Ranked Maps in Challenge mode (as Batman)
Fully upgrade a weapon in multiplayer
Defeat each of the enemy players at least once in a multiplayer match
Take down 6 different Elites in a match, using 6 different methods as Batman or Robin in multiplayer
As a Hero, defeat 4 Elites within 40 seconds without using melee in multiplayer
Obtain all the medals on Combat Training maps
Hear everything Alfred has to say
Complete all Dark Knight challenges
Master the Shadow Vigilante Dark Knight track
Use every Freeflow Focus gadget in one combo
Complete New Game Plus
Master the Worst Nightmare Dark Knight track
Acquire all upgrades
Take down 100 enemies who didn't know you were there
Master the Gotham Protector Dark Knight track
As an Elite, earn 4000 XP in a single multiplayer match
Collect every collectible
Complete all Most Wanted missions
Collect all Enigma items
Use the Batwing to travel to all Fast Travel points
Complete all Casefiles
Master the World's Greatest Detective Dark Knight track
Defeat the Joker
Capture all of Black Mask's Assassins
Decipher one Extortion File
Save a life
Glide 26 miles total
Stop 20 Crime in Progress
Successfully battle Shiva without taking any damage
Find the Black Mask
Complete a Most Wanted entry
Who is the Joker?
Glide across Bridge without touching ground
Shut down an entire Tower Network
Defeat Deathstroke
Complete a predator encounter without ever being spotted
Reach x50 Combo
Complete a predator encounter using only silent takedowns
Identify Black Mask's assassins
Stop Freeze and bring Boyle to justice
Perform 3 ice wall takedowns
Free all civilians frozen in cryogenic ice
Find all Activist tags in Cold, Cold Heart
Assemble the cryonucleation tunneller - the cryodrill
Stop Anarky thug operations in South Gotham
Takedown 2 enemies with one stalactite
Receive the Extreme Environment Suit (XE Suit)
Get 3 enemies frozen in one attack
Take no damage when playing as Bruce Wayne