I feel your pain. It was a bitch to do. I'm not going to say it was easy, because it wasn't. We tried a few different ways. We popped a bubble around him and wasted him with swords with 3 min left on the clock, but by then there was too many ads to clean up even with the 3 minutes. We then just ran in, wasted the ads and the blights, and when the room was pretty clear we started hitting the boss. Then we cleaned up more ads, hit the boss some more and when he died there was only a about a dozen ads left which we used swords, raid machine guns and shotguns. It was the only way that worked for us. Not gonna sit here and so oh dude it was easy. It sucked ass, but it is doable.