Zero was actually kind about it. His only request was that we use his gun to put him out of his misery after our mouths, Drift and Talon, tore out his heart. Because we had gotten the "heart" of Delphinus. I assured him it would be done. After all, I'm clever, aren't I? Never saw a gun before. Never held one, never fired one. But it's easy enough to determine how to use it.
So after those two ripped his ripcage open, I went to finish it. Mercy, isn't it?