When izek's eyes fall on them he sees some people wearing very modern clothes like a vest holding a shield and carrying some kind of weapons that he never saw. actually they were holding guns. But Izek was unaware of it. Izek though they might be from the natives side and natives group though they might be from the loner's side. Those people who suddenly appeared wasn't understanding they are coming towards them. They realize they are coming to attack them. They had no option but to fire. On that ambush many natives survivors civilians and also the loner's died. For the first time Izek got shot in amr. They were continuesly firing and izek was trying to save from them with his hand while didn't know the power of guns. He lost his one arm. After the reborn it was the first time he felt pain. Izek also got shot in his leg. He commended, "everybody fall back. It's not the right time to go forward right know. We don't know what weapon they are using." The natives groups was already accepted their defeat so they were also going back.
The people who appeared in that battle are from future. You remember when Izek was reborn, there was a massive earthquake and tsunami camed. It was that moment when timeline of the universe got broken. And some people from the future came up to past without knowing what happened and who knows same might be happened with those people who were in the past but currently are in the future.
.....IZEK WILL RETURN.....