How do I get good with Goremongers?

I'm still new to the game and just tried to do missions for the first time instead of killing each other. We aren't following the exact map layout as well. My only opponent has been Nemesis Claw and the score was 6 to 2. (As he was scoring points with each kill too) I only managed to kill most of his stuff with only 2 remaining but my entire squad was destroyed. I'm beginning to think Goremongers get countered by Nemesis Claw.