In order to unlock this achievement you must perform a single freeflow in which all variations of moves are completed in one combo.
This is extremely challenging and took me a while to master on the 360 version/
Challenges are perfect as you can restart if you mess up. 1st Wave of Sewer Bat Extreme Challenge is a great location to practice.
have purchased these upgrades:
Special Combo Throw, Combo Batarang, Combo Takedown Critical Combo Strikes, & Unlocked BatclawSequence
4) Cape Stun
5) Combo Batarang
6) Ground Takedown
8) Combo Takedown
The above sequence is not set in stone but a variation of all of the moves above must be completed in one single uninterrupted combo.I recommend watching a video
. It really helps you understand how to complete this.
Here is one by Achievement Hunter it helped me on the original game.https://www.youtube.com/watch?time_continue=13&v=8mFBYBW...
Here is a link to the original games trueachievement page with lots of various solutions