Yes there's a way to do it - BUT the only way you can achieve it is with your friends because you can tell them what to do. It's very simple actually, you need one person in a set place The first person by the cave itself - on top of the blue container near helicopters The second stands where the cave with the cabal is The third must kill all the Fallen that come out of the build where player 2 is. For this period of time only a single group of fallen will spawn. And then thats it. - what you actually just did was reset the spawning. Then to get the continuous spawning in the cave player one just needs to head to the build. Opposite the caves entrance. Hope this helps it has worked for me but nit every time