Crab Spider Assault Leader is a NPC ally you can find during the mission Provide relief against Wailers from Hardcase (CoV, levels 35 - 40). He is the leader of the failed assault on the Wailers of the Hard Way. He will be fighting a Wailer King when you find him first, and must be freed so he can help you. Once free, he will follow you and will attack any Wailer in his aggro range. If your char is one of those stealthy types, free him last. During my mission, the Crab Spider Assault leader had slightly less hit points that a Lieutenant of the same level.