Batman Arkham Origins - Shadow Vigilante Rank 5 (read description)

This is easy once u get the hang of it. you need to get into focus flow and win the fight without getting interrupted. Now when you start attacking, you can see you combo build up in white color number, keep building your combo and until 8 or so they will turn into yellow numbers which mean you can hit special takedown. But dont use any special take downs, instead keep fighting. once you reach 12 hits they will turn red. now just win the fighting without losing your combo. the best way to do this is keep jumping away from enemies and hit one at a time. fight may take long, but its a simple way.