Attributes: If they have to move to get to you, they only make one attack. Stand toe to toe and they attack twice.
Best Tactics: Fall back to a corridor with best armor in front. Front line: Attack or aid a ranged attack or dodge and then step back a space. Back line range attack and make sure the front folks can step back every time. Repeat. Do NOT give them a gap. They will swarm through it.
Note: They sometimes push and shove at the front fighters which might give them the gap they want.