Group two - fighters
As far as large fights against the biggest bads went, Nathan hadn't always been one to be right in the fray, as brother and daughters with healing abilities aside, he had a family to think about and his place as second-in-command meant there needed to be someone at AI when the Champion wasn't. He was a lawyer, not a superhero, and his interest in this fight wasn't just to help eliminate the resources of a bad guy before he came after even more of his family. His younger daughter was here and he'd known she wouldn't take no for an answer, despite the risks.
But it felt good to be there beyond just to keep an eye on Claire. And while she was proud of her badassness, he was prouder still. The Petrellis inheritance came with more bad than good in many ways, but steel determination when put to the wall was one thing he was glad he had passed on to her. And faded pain-sense or not, Nathan Petrelli would still cut down everything that even so much as tried to harm her or even impeded her from being able to do her work.
The smell and the sounds and even the sights as they descended lower were something that he hadn't entirely prepared for. It had been one thing to hear talk about this Hell on earth, it was another to see that it was so literal. If he hadn't been through one war, he might not have been able to tolerate it in a way that didn't leave him lunging for a corner, but even war casualties still wasn't enough to prepare anyone for the macabre sight as they gained entrance to a large room that in every way looked, felt and smelled like death.
After nodding to Leah and Scorpius in approval of the plan and the execution she had suggested, Nathan broke off from the main group with the few assigned to do so, systematically eliminating vampires and demons alike to clear the area of what was apparently one of the large 'torture chambers' while attempting to do a body count of those still alive, or recently dead, and those who might be beyond saving. Counting both those strapped down and those with knives and more in their hand was yet another reminder that the line of morality could be twisted so deeply sometimes.