I know where the splinters are and can quickly do away with the subjugaters and tormentor but run out of time waiting to go from room 2 to 3. Room one isn't bad. Room two takes 2 mins of killing ads before being able to advance to room 3. My last run had almost 4 mins of non-stop ads after shooting the splinters and tormentor. There shouldn't be any delays going from room to room.