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