Kill a Demon with the Helsing. [Bronze / 30G]

Location: The Dead City
You can do this in the chapter "The Dead City". In the very beginning of this chapter you will see a vision of a playground and some children. After that you will have to drop down to a small underground area. Here you can find the Helsing. It's at the very end of this underground area in a corner. Just a few minutes later you will encounter a demon (big winged creature) on a rooftop. Weaken the demon with your other weapons and kill it with the Helsing. If the demon dies too early you can still restart the checkpoint and try again.