is there any way to finish the worst nightmare challenges (number 6 in particular) when I already upgraded to proximity detonator?
The proximity detonator seems to block the takedown option.
Finishing predator challenges with proximity detonator
batman-arkham-origins
Best Answer
The Dark Knight Predator encounter #6 is by far the hardest.
It is absolutely possible to perform the explosive gel takedown, the easiest place to get this challenge is in the Bank. To perform the explosive gel takedown, you need to find a brick wall, not a wooden one. You have to place the gel on the opposite side of the wall from the enemy, when the gel explodes, it will send the fragments of the wall into the enemy killing them. There is no in game prompt for this happening and no visible verification that you succeeded until the stats rollup after the encounter.