Alma 25:13

13 And it came to pass that when the Lamanites saw that they could not overpower the Nephites they returned again to their own land; and many of them came over to dwell in the land of Ishmael and the land of Nephi, and did join themselves to the people of God, who were the people of Anti-Nephi-Lehi.

Wait. Why did the Lamonites suddenly want to join with the believers? To form a kind of alliance? Were their hearts softened toward these people that would rather die than kill? Especially after seeing the opposite kind of people that would torture and kill innocent people?

Who's heart wouldn't be softened by that?