Fear is the greatest tool in the world and not just for the evil.
It's fear that drove humans to evolve past their limits. Their fear of death, hunger, cold, and loss has pushed humanity and, in turn, the world forward.
And it was this kind of fear that Scart always wanted to impart to his enemies, he took from them the things they considered the most precious, and he collected them so that his victims feel fear of what else Scart might take next.
"You all will die here." The death of those he was responsible for hurt Amir. Ignoring the purpose, Amir had vowed to himself that no one in this group of his would die. But the fight hadn't even begun yet and there was already one of his men dead.