Police Brutality - 3 Medals [Robin] (Extreme)

The tail end of the grind of all the DLC trophies comes together. Let's pretend the mistake at 3:28 didn't happen. The key to getting the Wall Explosion Medal (at least for me) is to not take out anyone other than the Jammer Thug so that way there is more henchman to roam in front of the Weak Walls. I got lucky that they lined up so fast.