This achievement is story related and cannot be missed
*** Spoiler - click to reveal ***When you chasing after Gordon you will come to the medical facility and the morgue area. Batman will be infected by Scarecrow's gas and you will have to fight him in a nightmare-ish sequence. This is a little bit different from the other boss fights, but all in all very simple. Just try to keep out of his sight (indicated by a red light beam) and you should be good. Crouch whenever possible and take your time. At the end you will have to use gel on a wall and perform a well-timed jump. Head over to the batsignal light and flash Scarecrow. The achievement will unlock afterwards
(video credit: JcLGaming)
Hope this helps you guys!
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