When you unlock the creepy eye door in “The Broken Stairs” save your game. When you jump to the next building, there will be a cutscene and at the end you will be on the “Ancient One”. Now the trick here is to use
. It has a lock on feature where you can lock onto multiple targets even if they have flown behind you. At the beginning, you are going to want to focus on the angels, but make sure you're locking onto the other enemies too. They don’t take too much to kill and you need to get kills as fast as you can. When you get into the caves, you will see small little bugs in groups lock on, fire, and repeat as fast as you can.