Here is the full list of all 70 Batman: Return to Arkham - there are Arkham City achievements worth 1,500 gamerscore.
Obtain 114 medals on the original Arkham City and Nightwing Bundle Pack campaigns (as Nightwing)
Obtain 78 medals on the original Arkham City and Nightwing Bundle Pack ranked maps (as Nightwing)
Obtain 114 medals on the original Arkham City and Robin Bundle Pack campaigns (as Robin)
Obtain 78 medals on the original Arkham City and Robin Bundle Pack ranked maps (as Robin)
Have 12 murderous dates with Calendar Man
The joke's on who?
Defuse all bombs in 3 minutes or less
Snap Flash an unarmed thug, an armed thug, an environmental object and a Titan
Destroy all Harley Balloons
Clean up the Dry Docks
Find a way into the secret base
No crimefighter should be without this
Use 5 different Quickfire gadgets in one fight as Robin in Harley Quinn's Revenge
Zip Kick 5 different thugs
Shield Bash 5 different thugs
Obtain all 108 medals on the original Arkham City campaigns (as Catwoman)
Obtain all 72 medals on the original Arkham City ranked maps (as Catwoman)
Obtain all 108 medals on the original Arkham City campaigns (as Batman)
Main Story, Side Missions, Upgrades, Collectables, New Game Plus and Riddler's Revenge (as Batman)
Obtain 72 medals on the original Arkham City campaigns (as Batman)
Obtain 36 medals on the original Arkham City campaigns (as Batman)
Obtain all 72 medals on the original Arkham City ranked maps (as Batman)
Obtain 48 medals on the original Arkham City ranked maps (as Batman)
Obtain 24 medals on the original Arkham City ranked maps (as Batman)
Use 5 different Quickfire gadgets in one fight (any play mode)
Complete one combat challenge without taking damage (any character)
Perform a perfect combo including all of Batman's combat moves (any play mode)
Complete New Game Plus
Rescue all the hostages from Riddler
Rescue the fifth hostage from Riddler
Rescue the fourth hostage from Riddler
Rescue the third hostage from Riddler
Track down the serial killer
Reveal the mystery watcher
Stop the contract operative
Retrieve your stolen goods
Complete all 40 of the Catwoman Riddler grid items
Collect all of Batman's gadgets and upgrades
Stop all assaults in Arkham City
Collect enough evidence to locate the gun for hire
Rescue the second hostage from Riddler
Rescue the first hostage from Riddler
Reunite the separated couple
Destroy it all
Stop the phone booth killer
Time is running out
Answer the call for help
All the world is a stage
A moment of remembrance
Don't look down
Jump off the tallest building in Arkham City and glide for 1 minute without touching the ground.
Steal the score of a lifetime
Fight for survival
A deadly game of hide and seek
We are legion
Uncover the secret of Arkham City
Answer a ringing phone
Stop the unstoppable
Last man standing
Solve the first riddle
Clear the airwaves
Complete all augmented reality training exercises
Find someone to play remote Batarang catch with
Drop in on an old friend
Hammer the point home
Complete a combo of 50 moves (any play mode, any character)
There is only one way in
Save the medical volunteers
Save the damsel, but is she in distress?
Become the Bat